feat: remove legacy DocumentControls component

Remove deprecated DocumentControls from TestDrive JSUI plugin system:
- Remove document-controls.js from plugin asset list
- Remove script reference from HTML template
- Delete legacy document-controls files
- Consolidate all functionality into enhanced control panels

All control panel functionality now provided by enhanced controls:
- ContentsControl (NW): Table of contents and navigation
- StatusControl (E): Document status and metrics
- DebugControl (SE): Debug messages and system info
- EditControl (NE): Editing tools including Reset All button

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

markitect/templates/edit-mode-fixed.html

@@ -27,7 +27,6 @@
     <script src="markitect/static/js/core/debug-system.js"></script>
     <script src="markitect/static/js/core/section-manager.js"></script>
     <script src="markitect/static/js/components/debug-panel.js"></script>
-    <script src="markitect/static/js/components/document-controls.js"></script>
     <script src="markitect/static/js/components/dom-renderer.js"></script>
     <script src="markitect/static/js/controls/control-base.js"></script>
     <script src="markitect/static/js/controls/contents-control.js"></script>