feat: implement player logic and add arena assets for free mode

scenes/player.gd

@@ -256,8 +256,12 @@ func _ready():
 			
 		if name == str(multiplayer.get_unique_id()):
 			mat.set_shader_parameter("pointer_color", Color(0.0, 1.0, 0.0, 1.0)) # Green
+			if has_node("Name"):
+				$Name.modulate = Color(0.2, 0.8, 0.2, 1.0) # Pleasant Green for Name
 		else:
 			mat.set_shader_parameter("pointer_color", Color(1.0, 0.0, 0.0, 1.0)) # Red
+			if has_node("Name"):
+				$Name.modulate = Color.WHITE # White for others
 				
 		if pointer is MeshInstance3D:
 			pointer.material_override = mat
@@ -1117,6 +1121,10 @@ func attempt_target_action(target_index: int):
 		inventory_ui.deselect()
 
 func activate_powerup(effect_id: int):
+	if is_carrying_tekton or is_knock_mode or is_attack_mode:
+		NotificationManager.send_message(self, "Cannot use Power-Up right now!", NotificationManager.MessageType.WARNING)
+		return
+		
 	var main = get_tree().get_root().get_node_or_null("Main")
 	if not main or not main.ui_manager:
 		return
@@ -1146,6 +1154,10 @@ func activate_powerup(effect_id: int):
 
 func activate_held_powerup():
 	"""Finds whichever powerup is currently held and activates it."""
+	if is_carrying_tekton or is_knock_mode or is_attack_mode:
+		NotificationManager.send_message(self, "Cannot use Power-Up right now!", NotificationManager.MessageType.WARNING)
+		return
+		
 	var active_effect = -1
 	if special_tiles_manager:
 		for effect_key in special_tiles_manager.inventory: