Make on-device OCR a pluggable local service so it runs locally on every
platform (not just Windows), aimed at GoodNotes/Notability-class handwriting on
low-power hardware (e.g. Zen2 APU, CPU/iGPU).
- New OcrBackend abstraction (lib/services/ocr/): selector prefers an embedded
ONNX recognition backend, falling back to the OS-native backend (Windows
WinRT), and to a clean no-op when neither is available.
- OnnxRecognitionBackend: flutter_onnxruntime session from a bundled asset,
dart:ui preprocessing (resize to 48px, CHW float32, normalized), pure-Dart CTC
greedy decode. Fully guarded — absent model/dict is a no-op; never throws.
- ocr_engine.dart kept as a thin facade (recognizeImage) delegating to the
selector, so ocr_service.dart is unchanged.
- CtcDecoder unit-tested (6 tests). flutter analyze clean; all tests pass.
- Model is not committed; tool/fetch_ocr_model.sh + assets/models/ocr/README.md
document fetching PP-OCRv4 rec + dict on the dev machine.
- CI: forward HTTPS_PROXY to the Windows build so CMake can fetch the ONNX
Runtime native lib behind the GFW; README documents the system-install
alternative. PP-OCR geometry/blank assumptions documented for on-device tuning.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Bug fixes (Flutter):
- Wrap multi-statement DB writes (insert/update/delete note, deleteDocument,
deletePageData, OCR FTS merge, migrations) in transactions to prevent data
loss on interruption and a read-modify-write FTS race.
- Fix PdfDocument leaks on exception (try/finally dispose) and preserve image
aspect ratio when stamping images onto PDF pages.
- Guard file-picker against empty selection (was .single -> crash).
- Fix eraser ConcurrentModificationError and unmodifiable-list crash on PDF
pages; capture page synchronously on save to stop wrong-page data loss.
- Fix Riverpod DB-not-ready races, broken pull-to-refresh, settings load race,
and search N+1; transform stored annotations on PDF page rotation.
- Normalize pen pressure for devices without a pressure range.
- PPT: single source of truth for slide strokes so ink displays and exports.
UI/UX:
- Material 3 typography, theme-aware colors (dark-mode fixes), hover cursors
and right-click/visible actions on desktop, keyboard shortcuts (undo/redo/
save/find), toolbar overflow handling, friendlier empty states, semantic OCR
status badges, relative timestamps, 1-based page indicators, large-deck PPT
navigation, and a scratchpad-scope label in split view.
Server (optional backend):
- Persist JWT secret (was per-process random), block path traversal in storage,
fix CORS '*'+credentials, add OCR job ownership checks, last-writer-wins sync
guard, constant-time login, and split out heavy OCR deps so the API/tests run
without them.
CI: Gitea workflows for format+analyze+test (Linux, system sqlite) and a
Windows release build; pristine `flutter analyze`, all Flutter and server tests
green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
