game: add spawn rate to debug ui

scenes/managers/enemy_manager.gd

@@ -11,9 +11,10 @@ const ENEMY_RAT = preload("res://scenes/enemies/enemy_rat.tscn")
 
 
 func _ready() -> void:
-	timer.wait_time = spawn_rate / 1
+	timer.wait_time = 1 / spawn_rate
 	timer.start()
 	GlobalConst.sig_stop_spawning.connect(_on_stop_spawning)
+	GlobalConst.sig_set_spawn_rate.connect(_on_set_spawn_rate)
 
 
 func _on_timer_timeout() -> void:
@@ -25,9 +26,11 @@ func _on_timer_timeout() -> void:
 		new_enemy.target = target
 		add_child(new_enemy)
 
-
 func _on_stop_spawning(val: bool):
 	if val:
 		timer.stop()
 	elif timer.is_stopped():
 		timer.start()
+
+func _on_set_spawn_rate(val: float):
+	timer.wait_time = 1 / val