Improve JWT claims and chat channel reliability

Adds standard JWT claims (audience and issuer) to access tokens and updates config for these fields. Refactors multiplayer room chat channel logic to ensure reliable user join/leave with retry mechanisms, improves error handling and cleanup, and ensures host is correctly added as a participant. Updates Docker entrypoint for better compatibility and connection handling, modifies Docker Compose and Nginx config for improved deployment and proxy header forwarding.

app/config.py

@@ -77,6 +77,8 @@ class Settings(BaseSettings):
     secret_key: str = Field(default="your_jwt_secret_here", alias="jwt_secret_key")
     algorithm: str = "HS256"
     access_token_expire_minutes: int = 1440
+    jwt_audience: str = "5"
+    jwt_issuer: str | None = None
 
     # OAuth 设置
     osu_client_id: int = 5