Implement Phase 3: canvas drawing with stylus input
- PadCanvasView: custom View with stylus event handling (historical points
for smoothness), Path/Paint stroke rendering, backing bitmap at 1/4
resolution, 60pt grid drawing, Matrix coordinate transform
- CanvasState: tool modes (fine/medium pen, eraser, select), zoom/pan state
- EditorViewModel: loads/saves strokes to Room on completion
- EditorScreen: Compose wrapper with AndroidView + FilterChip toolbar
- NavGraph: pages route auto-navigates to first page editor, page size
passed through route params
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Kyle Isom
2fc4224f5a