Auto-play a random legal card when the turn timeout expires

server/README.md

@@ -51,6 +51,7 @@ All configuration comes from environment variables (see `.env.example`):
 | `OIDC_REDIRECT_URI` | `http://localhost:8080/auth/callback` | Login callback URL |
 | `GAME_TTL_SECONDS` | `86400` | Sliding TTL of a live game in Redis |
 | `HAND_ACK_TIMEOUT_SECONDS` | `30` | Seconds the between-hands scoring summary waits for acknowledgements |
+| `TURN_TIMEOUT_SECONDS` | `30` | Seconds a player has to play before the server plays a random legal card for them |
 | `APP_HOST` / `APP_PORT` | `0.0.0.0` / `8080` | Bind address |
 
 ## Data model
@@ -126,6 +127,15 @@ Client → server messages:
 
 After every accepted move the new state is broadcast to all four players.
 
+### Turn timeout
+
+The state carries a `turn_deadline` while a hand is being played. If the
+player on turn does not move before it, the server plays a random legal
+card for them (picking one of the legal captures at random when a capture
+is required), so a disconnected or idle player cannot stall the match. The
+timeout is `TURN_TIMEOUT_SECONDS` (default 30); the auto-played move is
+broadcast like any other.
+
 ### Hand-end summary
 
 When a hand finishes but the match continues, the game enters the