feat: comprehensive control panel UI improvements

- Fix version information display with actual Markitect version
- Implement auto-resize functionality with double-click on resize dot
- Add viewport repositioning to keep panels visible during auto-resize
- Reduce title bar height by 25% for more compact appearance
- Remove duplicate content titles below titlebars across all panels
- Optimize scrollbar positioning to right border with proper spacing
- Reposition resize dot to optimal corner location (bottom: 0px, right: -4px)
- Set default panel height to 1/3 of window height
- Fix Debug panel title formatting consistency
- Remove duplicate initialization warnings
- Clean up panel layout with proper margin management (10px bottom margin)

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

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

testdrive-jsui/static/css/controls.css

@@ -53,13 +53,7 @@
     font-family: monospace;
 }
 
-.debug-control .debug-header {
-    background: #343a40;
-    color: #fff;
-    padding: 0.5rem;
-    margin: -0.75rem -0.75rem 0.5rem -0.75rem;
-    border-radius: 5px 5px 0 0;
-}
+/* Removed debug-header styles - using base class title formatting */
 
 .debug-control .debug-logs {
     max-height: 200px;