gd: added input addon

addons/guide/guide_action_mapping.gd

@@ -0,0 +1,21 @@
+@icon("res://addons/guide/guide_internal.svg")
+@tool
+## An action to input mapping
+class_name GUIDEActionMapping
+extends Resource
+
+## The action to be mapped
+@export var action:GUIDEAction:
+	set(value):
+		if value == action:
+			return
+		action = value
+		emit_changed()
+
+## A set of input mappings that can trigger the action
+@export var input_mappings:Array[GUIDEInputMapping] = []:
+	set(value):
+		if value == input_mappings:
+			return
+		input_mappings = value
+		emit_changed()