Move help to JSON and add server docstrings

server/app/client.py

@@ -1,3 +1,5 @@
+"""Client connection model used by the signaling server."""
+
 from __future__ import annotations
 
 from dataclasses import dataclass
@@ -7,6 +9,8 @@ from websockets.asyncio.server import ServerConnection
 
 @dataclass
 class ClientConnection:
+    """Represents one connected websocket client and its world state."""
+
     websocket: ServerConnection
     id: str
     nickname: str = "user..."
@@ -14,4 +18,6 @@ class ClientConnection:
     y: int = 20
 
     def summary(self) -> dict[str, str | int]:
+        """Return a compact serializable snapshot for logs/diagnostics."""
+
         return {"id": self.id, "nickname": self.nickname, "x": self.x, "y": self.y}