Control Base Functionality Test

This page tests the improved ControlBase functionality. You should see:

1. Icon-only collapsed state: Controls start as small icons
2. Click to expand: Click the icon to expand the control
3. Drag functionality: When expanded, drag by the header to move
4. Bottom-left resize: When expanded, grab the ↙ corner to resize
5. Close button (✕): Returns control to original position
6. Header toggle: Click the title to show/hide content