- Add maximize/fullscreen button to standardized header bar
- Create useMaximize hook for shape utils to enable fullscreen
- Shape fills viewport when maximized, restores on Esc or toggle
- Implement on ChatBoxShapeUtil as example (other shapes can add easily)
- Button shows ⤢ for maximize, ⊡ for exit fullscreen
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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
