🗑️ remove Casbin dependency and related configurations

Remove Casbin package references, configurations, and unused imports across multiple files. This change simplifies the codebase by eliminating unnecessary dependencies and reducing complexity.

✨ add new chat features and improve message handling

Introduce new chat features including message notifications, nicknames, and improved message handling. Enhance the WebSocket service to support new packet handlers and improve message delivery.

🗃️ add new migrations for chat-related changes

Add new migrations to support the latest chat features, including changes to chat members, messages, and reactions. These migrations ensure the database schema is up-to-date with the latest code changes.

DysonNetwork.Sphere/Chat/ChatService.cs

@@ -1,9 +1,47 @@
-using DysonNetwork.Sphere;
-using DysonNetwork.Sphere.Chat;
+using DysonNetwork.Sphere.Account;
+using DysonNetwork.Sphere.Connection;
 using Microsoft.EntityFrameworkCore;
+using NodaTime;
 
-public class ChatService(AppDatabase db)
+namespace DysonNetwork.Sphere.Chat;
+
+public class ChatService(AppDatabase db, NotificationService nty, WebSocketService ws)
 {
+    public async Task<Message> SendMessageAsync(Message message, ChatMember sender, ChatRoom room)
+    {
+        db.ChatMessages.Add(message);
+        await db.SaveChangesAsync();
+        _ = DeliverMessageAsync(message, sender, room).ConfigureAwait(false);
+        return message;
+    }
+
+    public async Task DeliverMessageAsync(Message message, ChatMember sender, ChatRoom room)
+    {
+        var roomSubject = room.Realm is not null ? $"{room.Name}, {room.Realm.Name}" : room.Name;
+        var tasks = new List<Task>();
+        await foreach (
+            var member in db.ChatMembers
+                   .Where(m => m.ChatRoomId == message.ChatRoomId && m.AccountId != message.Sender.AccountId)
+                   .Where(m => m.Notify != ChatMemberNotify.None)
+                   .Where(m => m.Notify != ChatMemberNotify.Mentions || (message.MembersMetioned != null && message.MembersMetioned.Contains(m.Id)))
+                   .AsAsyncEnumerable()
+        )
+        {
+            ws.SendPacketToAccount(member.AccountId, new WebSocketPacket
+            {
+                Type = "messages.new",
+                Data = message
+            });
+            tasks.Add(nty.DeliveryNotification(new Notification
+            {
+                AccountId = member.AccountId,
+                Topic = "messages.new",
+                Title = $"{sender.Nick ?? sender.Account.Nick} ({roomSubject})",
+            }));
+        }
+        await Task.WhenAll(tasks);
+    }
+
     public async Task MarkMessageAsReadAsync(Guid messageId, long roomId, long userId)
     {
         var existingStatus = await db.ChatStatuses
@@ -45,4 +83,48 @@ public class ChatService(AppDatabase db)
 
         return messages.Count(m => !m.IsRead);
     }
+
+    public async Task<SyncResponse> GetSyncDataAsync(long roomId, long lastSyncTimestamp)
+    {
+        var timestamp = Instant.FromUnixTimeMilliseconds(lastSyncTimestamp);
+        var changes = await db.ChatMessages
+            .IgnoreQueryFilters()
+            .Where(m => m.ChatRoomId == roomId)
+            .Where(m => m.UpdatedAt > timestamp || m.DeletedAt > timestamp)
+            .Select(m => new MessageChange
+            {
+                MessageId = m.Id,
+                Action = m.DeletedAt != null ? "delete" : (m.EditedAt == null ? "create" : "update"),
+                Message = m.DeletedAt != null ? null : m,
+                Timestamp = m.DeletedAt != null ? m.DeletedAt.Value : m.UpdatedAt
+            })
+            .ToListAsync();
+
+        return new SyncResponse
+        {
+            Changes = changes,
+            CurrentTimestamp = SystemClock.Instance.GetCurrentInstant()
+        };
+    }
+}
+
+public class MessageChangeAction
+{
+    public const string Create = "create";
+    public const string Update = "update";
+    public const string Delete = "delete";
+}
+
+public class MessageChange
+{
+    public Guid MessageId { get; set; }
+    public string Action { get; set; } = null!;
+    public Message? Message { get; set; }
+    public Instant Timestamp { get; set; }
+}
+
+public class SyncResponse
+{
+    public List<MessageChange> Changes { get; set; } = [];
+    public Instant CurrentTimestamp { get; set; }
 }