Мелкий рефактор

apps/server-net/.editorconfig

@@ -1,6 +0,0 @@
-root = true
-
-[*.cs]
-csharp_prefer_braces = true:warning
-csharp_style_namespace_declarations = file_scoped:warning
-dotnet_diagnostic.IDE0011.severity = warning

apps/server-net/src/Host/Application/Admin/Commands/ResetUserPassword/ResetUserPasswordCommand.cs

@@ -28,11 +28,11 @@ internal sealed class ResetUserPasswordCommandHandler : ICommandHandler<ResetUse
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<SuccessResponse>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<SuccessResponse>(IdentityErrors.UserNotFound);
         }
 
         if (string.IsNullOrWhiteSpace(request.NewPassword)) 
-            return Result.Failure<SuccessResponse>(new Error("InvalidPassword", "Password cannot be empty"));
+            return Result.Failure<SuccessResponse>(DomainErrors.InvalidPassword);
 
         var hash = BCrypt.Net.BCrypt.HashPassword(request.NewPassword);
         user.ChangePassword(hash);

apps/server-net/src/Host/Application/Admin/Queries/GetUserDetails/GetUserDetailsQuery.cs

@@ -29,7 +29,7 @@ internal sealed class GetUserDetailsQueryHandler : IQueryHandler<GetUserDetailsQ
         var targetUser = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (targetUser == null)
         {
-            return Result.Failure<AdminUserDetailsDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<AdminUserDetailsDto>(IdentityErrors.UserNotFound);
         }
 
         var messagesCount = await _chatsDbContext.Messages.CountAsync(m => m.SenderId == request.UserId, cancellationToken);

apps/server-net/src/Host/Application/Federation/Commands/HandshakeFederationCommand.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using Knot.Shared.Kernel;
 using Knot.Shared.Kernel.Configuration;
 using Knot.Shared.Kernel.Constants;
@@ -31,11 +32,11 @@ internal sealed class HandshakeFederationCommandHandler : ICommandHandler<Handsh
             return Task.FromResult(Result.Failure<HandshakeResponse>(new Error(Errors.DisabledByAdmin, "Federation is disabled")));
 
         if (string.IsNullOrEmpty(request.Request.Domain) || string.IsNullOrEmpty(request.Request.PublicKey))
-            return Task.FromResult(Result.Failure<HandshakeResponse>(new Error("Request.Invalid", "Domain and PublicKey are required")));
+            return Task.FromResult(Result.Failure<HandshakeResponse>(DomainErrors.RequestInvalid));
 
         var allowedList = conf.AllowedDomains?.Select(d => d.Trim().ToLower()).ToList() ?? new System.Collections.Generic.List<string>();
         if (!allowedList.Contains(request.Request.Domain.ToLowerInvariant()))
-            return Task.FromResult(Result.Failure<HandshakeResponse>(new Error("Unauthorized", "Domain is not in the whitelist")));
+            return Task.FromResult(Result.Failure<HandshakeResponse>(StoryErrors.Unauthorized));
 
         using var rsa = RSA.Create(2048);
         var selfPublicKey = Convert.ToBase64String(rsa.ExportRSAPublicKey());

apps/server-net/src/Host/Application/Stories/Commands/AddStoryReaction/AddStoryReactionCommand.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -49,7 +50,7 @@ internal sealed class AddStoryReactionCommandHandler : ICommandHandler<AddStoryR
         var story = await _context.Stories.FindAsync(new object[] { request.StoryId }, cancellationToken);
         if (story == null)
         {
-            return Result.Failure<MessageResponse>(new Error("Story.NotFound", "Story not found"));
+            return Result.Failure<MessageResponse>(StoryErrors.StoryNotFound);
         }
 
         var existing = await _context.StoryReactions

apps/server-net/src/Host/Application/Stories/Commands/AddStoryReply/AddStoryReplyCommand.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -49,7 +50,7 @@ internal sealed class AddStoryReplyCommandHandler : ICommandHandler<AddStoryRepl
         var story = await _context.Stories.FindAsync(new object[] { request.StoryId }, cancellationToken);
         if (story == null)
         {
-            return Result.Failure<MessageResponse>(new Error("Story.NotFound", "Story not found"));
+            return Result.Failure<MessageResponse>(StoryErrors.StoryNotFound);
         }
 
         var reply = new StoryReply(request.StoryId, request.UserId, request.Content);

apps/server-net/src/Host/Application/Stories/Commands/DeleteStory/DeleteStoryCommand.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using System;
 using System.Threading;
 using System.Threading.Tasks;
@@ -24,11 +25,11 @@ internal sealed class DeleteStoryCommandHandler : ICommandHandler<DeleteStoryCom
         var story = await _context.Stories.FindAsync(new object[] { request.StoryId }, cancellationToken);
         if (story == null)
         {
-            return Result.Failure<MessageResponse>(new Error("Story.NotFound", "Story not found"));
+            return Result.Failure<MessageResponse>(StoryErrors.StoryNotFound);
         }
         if (story.UserId != request.UserId)
         {
-            return Result.Failure<MessageResponse>(new Error("Unauthorized", "Unauthorized"));
+            return Result.Failure<MessageResponse>(StoryErrors.Unauthorized);
         }
 
         _context.Stories.Remove(story);

apps/server-net/src/Host/Application/Stories/Commands/ViewStory/ViewStoryCommand.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using System;
 using System.Linq;
 using System.Threading;
@@ -38,7 +39,7 @@ internal sealed class ViewStoryCommandHandler : ICommandHandler<ViewStoryCommand
 
             if (story == null)
             {
-                return Result.Failure<MessageResponse>(new Error("Story.NotFound", "Story not found"));
+                return Result.Failure<MessageResponse>(StoryErrors.StoryNotFound);
             }
 
             if (story.UserId == request.UserId)

apps/server-net/src/Host/Application/Stories/Queries/GetStoryReplies/GetStoryRepliesQuery.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -33,11 +34,11 @@ internal sealed class GetStoryRepliesQueryHandler : IQueryHandler<GetStoryReplie
 
         if (story == null)
         {
-            return Result.Failure<List<StoryReplyDto>>(new Error("Story.NotFound", "Story not found"));
+            return Result.Failure<List<StoryReplyDto>>(StoryErrors.StoryNotFound);
         }
         if (story.UserId != request.UserId)
         {
-            return Result.Failure<List<StoryReplyDto>>(new Error("Unauthorized", "Unauthorized"));
+            return Result.Failure<List<StoryReplyDto>>(StoryErrors.Unauthorized);
         }
 
         var replies = new List<StoryReplyDto>();

apps/server-net/src/Host/Application/Stories/Queries/GetStoryViewers/GetStoryViewersQuery.cs

@@ -1,3 +1,4 @@
+using Host.Application.Stories;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -33,11 +34,11 @@ internal sealed class GetStoryViewersQueryHandler : IQueryHandler<GetStoryViewer
 
         if (story == null)
         {
-            return Result.Failure<List<StoryViewerDto>>(new Error("Story.NotFound", "Story not found"));
+            return Result.Failure<List<StoryViewerDto>>(StoryErrors.StoryNotFound);
         }
         if (story.UserId != request.UserId)
         {
-            return Result.Failure<List<StoryViewerDto>>(new Error("Unauthorized", "Unauthorized"));
+            return Result.Failure<List<StoryViewerDto>>(StoryErrors.Unauthorized);
         }
 
         var viewerIds = story.Viewers.Select(v => v.UserId).ToList();

apps/server-net/src/Host/Application/Stories/Queries/GetUserStories/GetUserStoriesQuery.cs

@@ -39,7 +39,7 @@ internal sealed class GetUserStoriesQueryHandler : IQueryHandler<GetUserStoriesQ
         var user = await _userRepository.GetByIdAsync(request.TargetUserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<StoryGroupDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<StoryGroupDto>(IdentityErrors.UserNotFound);
         }
 
         var result = new StoryGroupDto(

apps/server-net/src/Host/Application/Stories/StoryErrors.cs

@@ -0,0 +1,9 @@
+using Knot.Shared.Kernel;
+
+namespace Host.Application.Stories;
+
+public static class StoryErrors
+{
+    public static readonly Error Unauthorized = new Error("Unauthorized", "Access denied");
+    public static readonly Error StoryNotFound = new Error("Story.NotFound", "Story not found");
+}

apps/server-net/src/Modules/Chats/Application/Chats/Avatar/Avatar.cs

@@ -33,7 +33,7 @@ internal sealed class UploadGroupAvatarCommandHandler : ICommandHandler<UploadGr
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<Guid>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<Guid>(ChatErrors.ChatNotFound);
         }
 
         var fileId = await _fileStorage.UploadFileAsync(request.FileStream, request.FileName, request.ContentType);
@@ -67,7 +67,7 @@ internal sealed class CropGroupAvatarCommandHandler : ICommandHandler<CropGroupA
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<Guid>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<Guid>(ChatErrors.ChatNotFound);
         }
 
         string url;
@@ -117,7 +117,7 @@ internal sealed class RemoveGroupAvatarCommandHandler : ICommandHandler<RemoveGr
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<Guid>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<Guid>(ChatErrors.ChatNotFound);
         }
 
         chat.UpdateAvatar(null);

apps/server-net/src/Modules/Chats/Application/Chats/Clear/ClearChat.cs

@@ -25,7 +25,7 @@ internal sealed class ClearChatCommandHandler : ICommandHandler<ClearChatCommand
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<MessageResponse>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<MessageResponse>(ChatErrors.ChatNotFound);
         }
 
         // Currently a placeholder

apps/server-net/src/Modules/Chats/Application/Chats/GetChatById/GetChatById.cs

@@ -36,7 +36,7 @@ internal sealed class GetChatByIdQueryHandler : IQueryHandler<GetChatByIdQuery,
 
         if (!chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<ChatDto?>(new Error("Chats.Forbidden", "Вы не являетесь участником этого чата."));
+            return Result.Failure<ChatDto?>(ChatErrors.ChatsForbidden);
         }
 
         var userIdsToFetch = new HashSet<Guid>();

apps/server-net/src/Modules/Chats/Application/Chats/LeaveOrDelete/LeaveOrDeleteChat.cs

@@ -1,3 +1,4 @@
+
 using System;
 using System.Threading;
 using System.Threading.Tasks;
@@ -32,7 +33,7 @@ internal sealed class LeaveOrDeleteChatCommandHandler : ICommandHandler<LeaveOrD
 
         if (!chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<SuccessResponse>(new Error("Unauthorized", "Access denied"));
+            return Result.Failure<SuccessResponse>(ChatErrors.Unauthorized);
         }
 
         if (chat.Type == ChatType.Group)

apps/server-net/src/Modules/Chats/Application/Chats/Members/Members.cs

@@ -28,7 +28,7 @@ internal sealed class AddMembersCommandHandler : ICommandHandler<AddMembersComma
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<Guid>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<Guid>(ChatErrors.ChatNotFound);
         }
 
         foreach (var userId in request.UserIdsToAdd)
@@ -60,7 +60,7 @@ internal sealed class RemoveMemberCommandHandler : ICommandHandler<RemoveMemberC
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<Guid>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<Guid>(ChatErrors.ChatNotFound);
         }
 
         chat.RemoveMember(request.UserIdToRemove);

apps/server-net/src/Modules/Chats/Application/Chats/TogglePin/TogglePin.cs

@@ -28,13 +28,13 @@ internal sealed class TogglePinCommandHandler : ICommandHandler<TogglePinCommand
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null)
         {
-            return Result.Failure<TogglePinResponse>(new Error("Chat.NotFound", "Chat not found"));
+            return Result.Failure<TogglePinResponse>(ChatErrors.ChatNotFound);
         }
 
         var member = chat.Members.FirstOrDefault(m => m.UserId == request.UserId);
         if (member == null)
         {
-            return Result.Failure<TogglePinResponse>(new Error("Chat.NotFound", "Member not found"));
+            return Result.Failure<TogglePinResponse>(ChatErrors.ChatNotFound);
         }
 
         member.TogglePin();

apps/server-net/src/Modules/Chats/Application/Chats/Update/UpdateChat.cs

@@ -27,7 +27,7 @@ internal sealed class UpdateChatCommandHandler : ICommandHandler<UpdateChatComma
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<Guid>(new Error("Chat.NotFound", "Chat not found or access denied"));
+            return Result.Failure<Guid>(ChatErrors.ChatNotFound);
         }
 
         if (request.Name != null)

apps/server-net/src/Modules/Chats/Application/Messages/GetMessages/GetMessagesQuery.cs

@@ -32,7 +32,7 @@ internal sealed class GetMessagesQueryHandler : IQueryHandler<GetMessagesQuery,
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<List<MessageDetailDto>>(new Error("Chats.Forbidden", "Вы не являетесь участником этого чата."));
+            return Result.Failure<List<MessageDetailDto>>(ChatErrors.ChatsForbidden);
         }
 
         DateTime? cursorDate = null;
@@ -41,7 +41,7 @@ internal sealed class GetMessagesQueryHandler : IQueryHandler<GetMessagesQuery,
             cursorDate = parsed.ToUniversalTime();
         }
 
-        var messages = await _messageRepository.GetChatMessagesCursorAsync(request.ChatId, cursorDate, 100, cancellationToken);
+        var messages = await _messageRepository.GetChatMessagesCursorAsync(request.ChatId, cursorDate, ChatConstants.DefaultMessageQueryLimit, cancellationToken);
         var result = new List<MessageDetailDto>();
 
         var userIdsToFetch = new HashSet<Guid>();

apps/server-net/src/Modules/Chats/Application/Messages/GetSharedMedia/GetSharedMediaQuery.cs

@@ -33,10 +33,10 @@ internal sealed class GetSharedMediaQueryHandler : IQueryHandler<GetSharedMediaQ
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat == null || !chat.Members.Any(m => m.UserId == request.UserId))
         {
-            return Result.Failure<List<SharedMediaDto>>(new Error("Chats.Forbidden", "Вы не являетесь участником этого чата."));
+            return Result.Failure<List<SharedMediaDto>>(ChatErrors.ChatsForbidden);
         }
 
-        var messages = await _messageRepository.GetChatMessagesAsync(request.ChatId, 300, 0, cancellationToken);
+        var messages = await _messageRepository.GetChatMessagesAsync(request.ChatId, ChatConstants.MaxSharedMediaQueryLimit, 0, cancellationToken);
         messages = messages.Where(m => !m.IsDeleted && !m.DeletedByUsers.Contains(request.UserId)).ToList();
 
         var result = new List<SharedMediaDto>();

apps/server-net/src/Modules/Chats/Application/Messages/React/AddReactionCommand.cs

@@ -57,7 +57,7 @@ public sealed class AddReactionCommandHandler : ICommandHandler<AddReactionComma
         if (!success)
         {
             _logger.LogWarning("AddReaction: Message not found {MessageId}", request.MessageId);
-            return Result.Failure(new Error("Messages.NotFound", "Message not found."));
+            return Result.Failure(ChatErrors.MessagesNotFound);
         }
 
         await _unitOfWork.SaveChangesAsync(cancellationToken);

apps/server-net/src/Modules/Chats/Application/Messages/Send/SendMessageCommandHandler.cs

@@ -44,13 +44,13 @@ public sealed class SendMessageCommandHandler : ICommandHandler<SendMessageComma
         var chat = await _chatRepository.GetByIdAsync(request.ChatId, cancellationToken);
         if (chat is null)
         {
-            return Result.Failure<Guid>(new Error("Chats.NotFound", "Чат не найден."));
+            return Result.Failure<Guid>(ChatErrors.ChatsNotFound);
         }
 
         // 2. Проверяем, является ли отправитель участником
         if (!chat.Members.Any(m => m.UserId == request.SenderId))
         {
-            return Result.Failure<Guid>(new Error("Chats.Forbidden", "Вы не являетесь участником этого чата."));
+            return Result.Failure<Guid>(ChatErrors.ChatsForbidden);
         }
 
         // 3. Создаем сообщение

apps/server-net/src/Modules/Chats/Application/Messages/UploadFile/UploadFileCommand.cs

@@ -1,4 +1,5 @@
-using System;
+using Knot.Modules.Chats.Domain;
+using System;
 using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
@@ -27,13 +28,13 @@ internal sealed class UploadFileCommandHandler : ICommandHandler<UploadFileComma
     {
         if (request.Length == 0)
         {
-            return Result.Failure<UploadFileResponseDto>(new Error("File.Empty", "No file uploaded"));
+            return Result.Failure<UploadFileResponseDto>(ChatErrors.FileEmpty);
         }
 
         var maxMb = _settingsService.Current.MaxFileSizeMb;
         if (request.Length > maxMb * 1024 * 1024)
         {
-            return Result.Failure<UploadFileResponseDto>(new Error("File.TooLarge", $"File exceeds the maximum allowed size of {maxMb}MB."));
+            return Result.Failure<UploadFileResponseDto>(ChatErrors.FileTooLarge(maxMb));
         }
 
         var fileId = await _fileStorage.UploadFileAsync(request.FileStream, request.FileName, request.ContentType);

apps/server-net/src/Modules/Chats/Application/TelegramImport/AnalyzeImportCommand.cs

@@ -1,3 +1,4 @@
+using Knot.Modules.Chats.Domain;
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -28,12 +29,12 @@ internal sealed class AnalyzeImportCommandHandler : ICommandHandler<AnalyzeImpor
     {
         if (request.FileStream == null || request.FileStream.Length == 0)
         {
-            return Result.Failure<AnalyzeImportResponseDto>(new Error("File.Empty", "No file uploaded"));
+            return Result.Failure<AnalyzeImportResponseDto>(ChatErrors.FileEmpty);
         }
 
         if (!request.FileName.EndsWith(".zip", StringComparison.OrdinalIgnoreCase))
         {
-            return Result.Failure<AnalyzeImportResponseDto>(new Error("File.InvalidExtension", "Must be a ZIP archive"));
+            return Result.Failure<AnalyzeImportResponseDto>(ChatErrors.FileInvalidExtension);
         }
 
         var token = Guid.NewGuid();

apps/server-net/src/Modules/Chats/Application/TelegramImport/ExecuteImportCommand.cs

@@ -56,12 +56,12 @@ internal sealed class ExecuteImportCommandHandler : ICommandHandler<ExecuteImpor
     {
         if (!TelegramImportState.TempZips.TryGetValue(request.Token, out var tempPath))
         {
-            return Result.Failure<ExecuteImportResponseDto>(new Error("Import.Expired", "Session not found or expired"));
+            return Result.Failure<ExecuteImportResponseDto>(ChatErrors.ImportExpired);
         }
 
         if (!System.IO.File.Exists(tempPath))
         {
-            return Result.Failure<ExecuteImportResponseDto>(new Error("Import.Missing", "ZIP file lost"));
+            return Result.Failure<ExecuteImportResponseDto>(ChatErrors.ImportMissing);
         }
 
         var myId = request.CurrentUserId;
@@ -95,7 +95,7 @@ internal sealed class ExecuteImportCommandHandler : ICommandHandler<ExecuteImpor
                 var res = await _sender.Send(command, cancellationToken);
                 if (res.IsFailure)
                 {
-                    return Result.Failure<ExecuteImportResponseDto>(new Error("Import.CreateChatFailed", res.Error.Description ?? res.Error.Code));
+                    return Result.Failure<ExecuteImportResponseDto>(ChatErrors.ImportCreateChatFailed(res.Error.Description ?? res.Error.Code));
                 }
 
                 chatId = res.Value;
@@ -107,7 +107,7 @@ internal sealed class ExecuteImportCommandHandler : ICommandHandler<ExecuteImpor
             var res = await _sender.Send(command, cancellationToken);
             if (res.IsFailure)
             {
-                return Result.Failure<ExecuteImportResponseDto>(new Error("Import.CreateChatFailed", res.Error.Description ?? res.Error.Code));
+                return Result.Failure<ExecuteImportResponseDto>(ChatErrors.ImportCreateChatFailed(res.Error.Description ?? res.Error.Code));
             }
 
             chatId = res.Value;

apps/server-net/src/Modules/Chats/Domain/ChatConstants.cs

@@ -0,0 +1,9 @@
+namespace Knot.Modules.Chats.Domain;
+
+public static class ChatConstants
+{
+    public const int DefaultMessageQueryLimit = 100;
+    public const int MaxSharedMediaQueryLimit = 300;
+    public const int SearchMessagesLimit = 50;
+    public const int MaxFileUploadSizeMb = 50;
+}

apps/server-net/src/Modules/Chats/Domain/ChatErrors.cs

@@ -0,0 +1,19 @@
+using Knot.Shared.Kernel;
+
+namespace Knot.Modules.Chats.Domain;
+
+public static class ChatErrors
+{
+    public static readonly Error FileEmpty = new Error("File.Empty", "No file uploaded");
+    public static readonly Error FileInvalidExtension = new Error("File.InvalidExtension", "Must be a ZIP archive");
+    public static readonly Error ImportExpired = new Error("Import.Expired", "Session not found or expired");
+    public static readonly Error ImportMissing = new Error("Import.Missing", "ZIP file lost");
+    public static readonly Error ChatNotFound = new Error("Chat.NotFound", "Chat not found or access denied");
+    public static readonly Error ChatsForbidden = new Error("Chats.Forbidden", "Вы не являетесь участником этого чата.");
+    public static readonly Error MessagesNotFound = new Error("Messages.NotFound", "Message not found.");
+    public static readonly Error ChatsNotFound = new Error("Chats.NotFound", "Чат не найден.");
+    public static readonly Error Unauthorized = new Error("Chats.Unauthorized", "Access denied");
+
+    public static Error ImportCreateChatFailed(string msg) => new Error("Import.CreateChatFailed", msg);
+    public static Error FileTooLarge(int maxMb) => new Error("File.TooLarge", $"File exceeds the maximum allowed size of {maxMb}MB.");
+}

apps/server-net/src/Modules/Chats/Infrastructure/Persistence/MessageRepository.cs

@@ -74,7 +74,7 @@ public sealed class MessageRepository : IMessageRepository
 
         return await q.Where(m => m.Content != null && m.Content.Contains(query))
             .OrderByDescending(m => m.CreatedAt)
-            .Take(50)
+            .Take(ChatConstants.SearchMessagesLimit)
             .Include(m => m.Media)
             .Include(m => m.ReadBy)
             .Include(m => m.Reactions)

apps/server-net/src/Modules/Identity/Application/Friends/AcceptFriendRequest.cs

@@ -1,3 +1,4 @@
+using Knot.Modules.Identity.Domain;
 using System;
 using System.Threading;
 using System.Threading.Tasks;
@@ -24,7 +25,7 @@ internal sealed class AcceptFriendRequestCommandHandler : ICommandHandler<Accept
         var friendship = await _context.Friendships.FindAsync(new object[] { request.FriendshipId }, cancellationToken);
         if (friendship == null || friendship.FriendId != request.UserId)
         {
-            return Result.Failure<Guid>(new Error("Friends.NotFound", "Request not found"));
+            return Result.Failure<Guid>(IdentityErrors.FriendsNotFound);
         }
 
         friendship.Accept();

apps/server-net/src/Modules/Identity/Application/Friends/DeclineFriendRequest.cs

@@ -1,3 +1,4 @@
+using Knot.Modules.Identity.Domain;
 using System;
 using System.Threading;
 using System.Threading.Tasks;
@@ -24,7 +25,7 @@ internal sealed class DeclineFriendRequestCommandHandler : ICommandHandler<Decli
         var friendship = await _context.Friendships.FindAsync(new object[] { request.FriendshipId }, cancellationToken);
         if (friendship == null || friendship.FriendId != request.UserId)
         {
-            return Result.Failure(new Error("Friends.NotFound", "Request not found"));
+            return Result.Failure(IdentityErrors.FriendsNotFound);
         }
 
         friendship.Decline();

apps/server-net/src/Modules/Identity/Application/Friends/RemoveFriend.cs

@@ -1,3 +1,4 @@
+using Knot.Modules.Identity.Domain;
 using System;
 using System.Threading;
 using System.Threading.Tasks;
@@ -24,7 +25,7 @@ internal sealed class RemoveFriendCommandHandler : ICommandHandler<RemoveFriendC
         var friendship = await _context.Friendships.FindAsync(new object[] { request.FriendshipId }, cancellationToken);
         if (friendship == null || (friendship.UserId != request.UserId && friendship.FriendId != request.UserId))
         {
-            return Result.Failure(new Error("Friends.NotFound", "Friendship not found"));
+            return Result.Failure(IdentityErrors.FriendsNotFound);
         }
 
         _context.Friendships.Remove(friendship);

apps/server-net/src/Modules/Identity/Application/Friends/SendFriendRequest.cs

@@ -25,7 +25,7 @@ internal sealed class SendFriendRequestCommandHandler : ICommandHandler<SendFrie
     {
         if (request.UserId == request.FriendId)
         {
-            return Result.Failure(new Error("Friends.Self", "Cannot add yourself"));
+            return Result.Failure(IdentityErrors.FriendsSelf);
         }
 
         var existing = await _context.Friendships
@@ -34,7 +34,7 @@ internal sealed class SendFriendRequestCommandHandler : ICommandHandler<SendFrie
 
         if (existing != null)
         {
-            return Result.Failure(new Error("Friends.Exists", "Friendship already exists"));
+            return Result.Failure(IdentityErrors.FriendsExists);
         }
 
         var friendship = Friendship.Create(request.UserId, request.FriendId);

apps/server-net/src/Modules/Identity/Application/Users/Avatar/CropAvatar.cs

@@ -27,7 +27,7 @@ internal sealed class CropAvatarCommandHandler : ICommandHandler<CropAvatarComma
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<UserProfileDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<UserProfileDto>(IdentityErrors.UserNotFound);
         }
 
         string avatarUrl;

apps/server-net/src/Modules/Identity/Application/Users/Avatar/DeleteAvatar.cs

@@ -22,7 +22,7 @@ internal sealed class DeleteAvatarCommandHandler : ICommandHandler<DeleteAvatarC
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<UserProfileDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<UserProfileDto>(IdentityErrors.UserNotFound);
         }
 
         user.UpdateAvatar(null);

apps/server-net/src/Modules/Identity/Application/Users/Avatar/UploadAvatar.cs

@@ -25,7 +25,7 @@ internal sealed class UploadAvatarCommandHandler : ICommandHandler<UploadAvatarC
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<UserProfileDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<UserProfileDto>(IdentityErrors.UserNotFound);
         }
 
         var fileId = await _fileStorage.UploadFileAsync(request.FileStream, request.FileName, request.ContentType);

apps/server-net/src/Modules/Identity/Application/Users/GetMe/GetMe.cs

@@ -21,7 +21,7 @@ internal sealed class GetMeQueryHandler : IQueryHandler<GetMeQuery, AuthResponse
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<AuthResponseDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<AuthResponseDto>(IdentityErrors.UserNotFound);
         }
 
         var response = new AuthResponseDto(

apps/server-net/src/Modules/Identity/Application/Users/GetUser/GetUser.cs

@@ -20,7 +20,7 @@ internal sealed class GetUserQueryHandler : IQueryHandler<GetUserQuery, UserProf
         var user = await _userRepository.GetByIdAsync(request.Id, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<UserProfileDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<UserProfileDto>(IdentityErrors.UserNotFound);
         }
 
         var dto = new UserProfileDto(

apps/server-net/src/Modules/Identity/Application/Users/Login/LoginUserCommandHandler.cs

@@ -28,7 +28,7 @@ public sealed class LoginUserCommandHandler : ICommandHandler<LoginUserCommand,
 
         if (user is null || !BCrypt.Net.BCrypt.Verify(request.Password, user.PasswordHash))
         {
-            return Result.Failure<AuthResponseDto>(new Error("Identity.InvalidCredentials", "Неверное имя пользователя или пароль."));
+            return Result.Failure<AuthResponseDto>(IdentityErrors.IdentityInvalidCredentials);
         }
 
         string token = _tokenProvider.Generate(user);

apps/server-net/src/Modules/Identity/Application/Users/Register/RegisterUserCommandHandler.cs

@@ -43,13 +43,13 @@ public sealed class RegisterUserCommandHandler : ICommandHandler<RegisterUserCom
     {
         if (!_settings.Current.EnableRegistration)
         {
-            return Result.Failure<AuthResponseDto>(new Error("Identity.RegistrationDisabled", "Registration is disabled by the administrator."));
+            return Result.Failure<AuthResponseDto>(IdentityErrors.IdentityRegistrationDisabled);
         }
 
         // 1. Проверка уникальности username
         if (!await _userRepository.IsUsernameUniqueAsync(request.Username, cancellationToken))
         {
-            return Result.Failure<AuthResponseDto>(new Error("Identity.UsernameNotUnique", "Это имя пользователя уже занято."));
+            return Result.Failure<AuthResponseDto>(IdentityErrors.IdentityUsernameNotUnique);
         }
 
         // 2. Хеширование пароля (здесь будет вызов сервиса, пока заглушка)

apps/server-net/src/Modules/Identity/Application/Users/UpdateProfile/UpdateProfile.cs

@@ -22,7 +22,7 @@ internal sealed class UpdateProfileCommandHandler : ICommandHandler<UpdateProfil
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<UserProfileDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<UserProfileDto>(IdentityErrors.UserNotFound);
         }
 
         user.UpdateProfile(request.DisplayName ?? user.DisplayName, request.Bio, request.Birthday);

apps/server-net/src/Modules/Identity/Application/Users/UpdateSettings/UpdateSettings.cs

@@ -22,7 +22,7 @@ internal sealed class UpdateSettingsCommandHandler : ICommandHandler<UpdateSetti
         var user = await _userRepository.GetByIdAsync(request.UserId, cancellationToken);
         if (user == null)
         {
-            return Result.Failure<UserProfileDto>(new Error("User.NotFound", "User not found"));
+            return Result.Failure<UserProfileDto>(IdentityErrors.UserNotFound);
         }
 
         user.UpdateSettings(request.HideStoryViews ?? user.HideStoryViews);

apps/server-net/src/Modules/Identity/Domain/IdentityErrors.cs

@@ -0,0 +1,14 @@
+using Knot.Shared.Kernel;
+
+namespace Knot.Modules.Identity.Domain;
+
+public static class IdentityErrors
+{
+    public static readonly Error FriendsNotFound = new Error("Friends.NotFound", "Friendship not found");
+    public static readonly Error FriendsSelf = new Error("Friends.Self", "Cannot add yourself");
+    public static readonly Error FriendsExists = new Error("Friends.Exists", "Friendship already exists");
+    public static readonly Error UserNotFound = new Error("User.NotFound", "User not found");
+    public static readonly Error IdentityInvalidCredentials = new Error("Identity.InvalidCredentials", "Неверное имя пользователя или пароль.");
+    public static readonly Error IdentityRegistrationDisabled = new Error("Identity.RegistrationDisabled", "Registration is disabled by the administrator.");
+    public static readonly Error IdentityUsernameNotUnique = new Error("Identity.UsernameNotUnique", "Это имя пользователя уже занято.");
+}

apps/server-net/src/Shared/Knot.Shared.Kernel/DomainErrors.cs

@@ -0,0 +1,7 @@
+namespace Knot.Shared.Kernel;
+
+public static class DomainErrors
+{
+    public static readonly Error InvalidPassword = new Error("Admin.InvalidPassword", "Пароль не должен быть пустым.");
+    public static readonly Error RequestInvalid = new Error("Request.Invalid", "Invalid federation request");
+}