Desktop app with live scanning and OCR

tools/app.py (myscan/app.py, Qt/PySide6) shows the camera and the page as it
is stitched, Start/Stop or the scan button (F5), then reads the finished page
with RapidOCR (myscan/ocr.py; bundled multilingual models, offline). Lines are
outlined on the page by confidence and linked to an editable text pane that
can be copied or saved. Existing images can be opened or dropped, so the app
is useful without the mouse.

The scan loop moves from tools/scan.py to myscan/scanner.py, shared by both.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -19,6 +19,13 @@ Linux driver tools for the Hama myScan (00052343) scanner mouse, a Dacuda design
   `--view [PORT]` serves a live view at `http://<host>:8000/`: the camera, the page as it is stitched
   (re-solved every 1.5 s, current position outlined), Start/Stop buttons, PNG/JPEG download of the finished
   page and a Screenshot button (camera + page + status as one PNG)
+- `tools/app.py` — desktop app (Qt/PySide6; Linux, Windows, macOS): live camera and page view while scanning
+  (Start/Stop or the scan button, F5), then OCR of the finished page with RapidOCR (`myscan/ocr.py`;
+  multilingual PP-OCRv6 models bundled in the wheel, works offline). Recognised lines are outlined on the page by
+  confidence; click one to select its text, and the cursor in the text highlights its line. The text is editable
+  and can be copied or saved as .txt. `python tools/app.py [image]` also opens and reads existing images (Open, or
+  drag and drop), which is all it does on machines without the mouse
+- `myscan/scanner.py` — the scan loop shared by `scan.py` and the app (finds the mouse's `/dev/videoN` itself)
 - `myscan/live.py`, `myscan/webview.py` — the live preview and its browser viewer (standard library only)
 - `tools/record.py` — record a scan session: `python tools/record.py -d 25 -o scan_text`
 - `tools/stitch.py` — stitch a recording: `python tools/stitch.py scan_text` -> `scan_text/page.png`