feat: Implement core lobby system including UI, player management, and game mode settings.

scripts/managers/lobby_manager.gd

@@ -144,6 +144,13 @@ func leave_room() -> void:
 	"""Leave the current room."""
 	print("[LobbyManager] Leaving room. Clearing all local state.")
 	
+	# If we are the host, notify all clients to kick them back to menu/lobby
+	if is_host and multiplayer.has_multiplayer_peer() and multiplayer.is_server():
+		print("[LobbyManager] Host is leaving. Kicking all clients...")
+		# We use rpc() instead of .rpc() for compatibility with older Godot 4 versions if applicable, 
+		# but .rpc() is standard in 4.x. Let's stick to standard.
+		kick_all_clients.rpc()
+	
 	# Important: Reset all lobby settings and player lists first
 	reset()
 	
@@ -214,6 +221,16 @@ func _check_all_ready() -> void:
 func is_all_ready() -> bool:
 	return _all_ready
 
+@rpc("authority", "call_local", "reliable")
+func kick_all_clients() -> void:
+	"""Called on all clients when the host leaves to ensure they are returned to the menu."""
+	if not is_host:
+		print("[LobbyManager] Received kick from host. Returning to menu...")
+		disconnect_reason = "Host left the lobby. Room closed."
+		emit_signal("host_disconnected")
+		# We use call_deferred to avoid potential issues during RPC stack processing
+		call_deferred("leave_room")
+
 # =============================================================================
 # Game Start
 # =============================================================================
@@ -636,6 +653,14 @@ func _on_peer_connected(peer_id: int) -> void:
 
 func _on_peer_disconnected(peer_id: int) -> void:
 	"""Called when peer disconnects."""
+	print("Peer disconnected: ", peer_id)
+	
+	# If the host (peer 1) disconnected and we are not host, we should be kicked
+	if peer_id == 1 and not is_host:
+		print("[LobbyManager] Host peer disconnected. Kicking self...")
+		_on_server_disconnected()
+		return
+
 	for i in range(players_in_room.size()):
 		if players_in_room[i]["id"] == peer_id:
 			players_in_room.remove_at(i)
@@ -652,8 +677,9 @@ func _on_server_disconnected() -> void:
 	print("[LobbyManager] Server (Host) disconnected. Terminating room...")
 	disconnect_reason = "Host disconnected. Match terminated."
 	rematch_votes.clear()
-	emit_signal("host_disconnected")
+	# Ensure full cleanup and state reset
 	leave_room()
+	emit_signal("host_disconnected")
 
 # =============================================================================
 # Rematch Logic