Added default scene for interact areas

This way, we have a scene that has the default configuration (collision layers and mask) of the interact area already setup.
I made it this way instead of by modifying the interact_area.gd because I'd like to let the contributors modify the collision layers of the nodes after they were created.

I think that this would not be needed anymore once we this pull request is merged into godot and default values for inherited properties can be overriden: godotengine/godot#93787 -- godotengine/godot-proposals#338

Author: JuanFdS

scenes/interact/interact_area.tscn

@@ -0,0 +1,9 @@
+[gd_scene load_steps=2 format=3 uid="uid://dutgnbiy7xalb"]
+
+[ext_resource type="Script" uid="uid://du8wfijr35r35" path="res://scenes/interact/interact_area.gd" id="1_esvy3"]
+
+[node name="InteractArea" type="Area2D"]
+collision_layer = 32
+collision_mask = 0
+script = ExtResource("1_esvy3")
+metadata/_custom_type_script = "uid://du8wfijr35r35"