Add fully functional Snap Turn controls:
- Toggle button (Enabled/Disabled) with blue/gray color coding
- 5 angle buttons: 22.5°, 45°, 90°, 180°, 360°
- Selected button highlighted in blue with bold text
- Disabled appearance when snap is off (50% opacity)
- Wire up to appConfigInstance.setTurnSnap()
- Update UI from config observable changes
Follows same pattern as Rotation Snap section but for snap turning.
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Co-Authored-By: Claude <noreply@anthropic.com>
Michael Mainguy
3002181160