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

scenes/lobby.gd

@@ -7,6 +7,7 @@ extends Control
 @onready var browse_rooms_btn = $MainMenuPanel/VBoxContainer/ButtonSection/BrowseRoomsBtn
 @onready var main_menu_profile_btn = $MainMenuPanel/VBoxContainer/ButtonSection/ProfileBtn
 @onready var lobby_settings_btn = $MainMenuPanel/VBoxContainer/ButtonSection/SettingsBtn
+@onready var quit_btn = $MainMenuPanel/VBoxContainer/ButtonSection/QuitBtn
 
 # UI References - Server Selection
 @onready var server_option = $MainMenuPanel/VBoxContainer/ServerSelectionSection/ServerOption
@@ -142,6 +143,8 @@ func _ready():
 		lobby_settings_btn.pressed.connect(_on_settings_pressed)
 	if leaderboard_btn:
 		leaderboard_btn.pressed.connect(_on_leaderboard_pressed)
+	if quit_btn:
+		quit_btn.pressed.connect(_on_quit_pressed)
 	
 	# Connect Server Selection signals
 	if server_option:
@@ -585,6 +588,10 @@ func _on_logout_pressed() -> void:
 	AuthManager.logout()
 	_go_to_login()
 
+func _on_quit_pressed() -> void:
+	print("[Lobby] Quitting game...")
+	get_tree().quit()
+
 func _on_settings_pressed():
 	var settings_menu = get_node_or_null("SettingsMenu")
 	if not settings_menu: