fix(matrix-bridge): fix _SoakMatrixClient.mark_seen signature for inject endpoint

Made-with: Cursor

services/matrix-bridge-dagi/app/main.py

@@ -871,7 +871,7 @@ async def debug_inject_event(body: Dict[str, Any]) -> Dict[str, Any]:
             def __init__(self) -> None:  # noqa: D107
                 pass  # skip real __init__
 
-            async def mark_seen(self, room_id: str, event_id: str) -> None:  # type: ignore[override]
+            def mark_seen(self, event_id: str) -> None:  # type: ignore[override]
                 pass
 
             async def send_text(self, room_id: str, text: str,  # type: ignore[override]