fix: resolve JavaScript const redeclaration and MarkitectMain issues

**JavaScript Fixes:**
- Fixed const redeclaration error: removed duplicate MARKITECT_STRICT_MODE declaration from control-base.js
- Fixed MarkitectMain not available: updated plugin to load main-updated.js instead of main.js
- Added MARKITECT_STRICT_MODE declaration to main-updated.js for consistency
- Ensured only one main file is loaded to prevent conflicts

**Plugin Asset Updates:**
- Changed testdrive-jsui plugin asset list from main.js to main-updated.js
- Verified proper loading order and dependency resolution
- All JavaScript constants now declared exactly once

**Testing Infrastructure:**
- Comprehensive JavaScript fix verification test
- Browser-ready test file generation for manual verification
- Automated const declaration conflict detection
- Asset loading order validation

**Key Fixes:**
- ❌ "Uncaught SyntaxError: redeclaration of const MARKITECT_STRICT_MODE" → ✅ Resolved
- ❌ "⚠️ MarkitectMain not available, edit functionality may be limited" → ✅ Resolved
- ❌ Multiple main.js files causing conflicts → ✅ Single main-updated.js loaded

**Verification Results:**
```
✅ No const declaration conflicts
✅ MarkitectMain properly declared once
✅ Correct main-updated.js file loaded
✅ HTML references correct scripts
```

Browser console should now show:
- 🎯 "TestDrive JSUI loading complete, initializing..."
- 🚀 "Starting MarkitectMain initialization..."
- ✅ No redeclaration errors

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

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

markitect/plugins/testdrive_jsui.py

@@ -50,7 +50,7 @@ class TestDriveJSUIEngine(RenderingEnginePlugin):
                 "static/js/controls/debug-control.js",
                 "static/js/controls/edit-control.js",
                 "static/js/config-loader.js",
-                "static/js/main.js"
+                "static/js/main-updated.js"
             ],
             "css": [
                 "static/css/editor.css",