✨ Add chat message handling and WebSocket integration

Introduce new `ChatService` for managing chat messages, including marking messages as read and checking read status. Add `WebSocketPacket` class for handling WebSocket communication and integrate it with `WebSocketService` to process chat-related packets. Enhance `ChatRoom` and `ChatMember` models with additional fields and relationships. Update `AppDatabase` to include new chat-related entities and adjust permissions for chat creation.

DysonNetwork.Sphere/Realm/RealmChatController.cs

@@ -9,7 +9,7 @@ namespace DysonNetwork.Sphere.Realm;
 [Route("/realm/{slug}")]
 public class RealmChatController(AppDatabase db) : ControllerBase
 {
-    [HttpGet("/chat")]
+    [HttpGet("chat")]
     [Authorize]
     public async Task<ActionResult<List<ChatRoom>>> ListRealmChat(string slug)
     {