feat: add interactable base script

ruf-der-pilze/scripts/interactable.gd

@@ -0,0 +1,10 @@
+# Base class for all interactable objects in the world.
+# Attach to a StaticBody3D or Area3D that has a CollisionShape3D.
+# Override interact() in subclasses.
+class_name Interactable
+extends Node3D
+
+## Called when a player interacts with this object.
+## peer_id is the NetworkManager.my_id of the interacting player.
+func interact(_peer_id: int) -> void:
+	pass