feat: add input action and project setting mappings

src/Godot/Mappings/InputAction.cs

@@ -0,0 +1,30 @@
+using System;
+
+namespace Game.Godot.Mappings;
+
+public enum InputAction
+{
+    MoveLeft,
+    MoveRight,
+    MoveForward,
+    MoveBack,
+    Jump,
+    Cancel
+}
+
+public static class InputActionExtensions
+{
+    /// <summary>
+    /// Godot Input Map action name for this action.
+    /// </summary>
+    public static string ActionName(this InputAction action) => action switch
+    {
+        InputAction.MoveLeft => "move_left",
+        InputAction.MoveRight => "move_right",
+        InputAction.MoveForward => "move_forward",
+        InputAction.MoveBack => "move_back",
+        InputAction.Jump => "jump",
+        InputAction.Cancel => "ui_cancel",
+        _ => throw new ArgumentOutOfRangeException(nameof(action), action, null)
+    };
+}