Add working debug level with grass and soil tiles

- Created DebugLevel class that bypasses complex TiledLevel loader
- Simple platform with grass tiles (10.gif) on top, soil tiles (10.gif) underneath
- Fixed tile texture paths to work with MAPS_PATH
- Fixed null check in User.js to prevent server crashes
- Working physics collision with Box2D
- Clean test environment for physics engine migration

app/Game/Channel/Loader/DebugLevel.js

@@ -0,0 +1,19 @@
+define([
+    "Game/Core/Loader/DebugLevel"
+],
+
+function (Parent) {
+
+    "use strict";
+
+    function DebugLevel(uid, engine) {
+        Parent.call(this, uid, engine);
+    }
+
+    DebugLevel.prototype = Object.create(Parent.prototype);
+
+    // Channel side doesn't need any special handling beyond the core functionality
+    // The physics engine and tile creation is handled by the parent class
+
+    return DebugLevel;
+});