Overhaul viewer overlay with a unified bottom toolbar, dark theme support,
theme toggle, camera orbit/top-view controls, and fix TypeScript array
access errors for level and wall mode cycling.
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
- Add reusable ActionButton component with tooltip and shortcut display
- Add keyboard shortcuts dialog in settings panel
- Fix ButtonProps import error (derive type from Button component)
- Fix AnyNodeId type mismatch in tree-node-actions visibility toggle
- Various UI refinements across action menu, sidebar, and editor
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
