Update to v2.0.0: 3D axis lines with arrow key support

- Version bumped to 2.0.0
- Added 3D axis line creation (arrow keys: ↑=Z, ↓=Y, ←/→=X)
- Two-phase command workflow: pick start point, then select axis or second point
- Cross-platform keyboard event handling (Windows VK + macOS Carbon codes)
- Live preview feedback during axis/point selection
- Updated manifest with new features

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
