Added game over screen

menu/game_over_screen.gd

@@ -0,0 +1,21 @@
+extends Control
+
+
+signal show_main_menu
+
+
+@onready var main_menu_button : Button = $%MainMenuButton
+@onready var button_focus_timer : Timer = $ButtonFocusTimer
+
+
+func _on_timer_timeout() -> void:
+	main_menu_button.grab_focus()
+
+
+func _on_main_menu_button_pressed() -> void:
+	show_main_menu.emit()
+
+
+func _on_visibility_changed() -> void:
+	if visible and button_focus_timer:
+		button_focus_timer.start()