fix(cli): preserve notes during sync moves

- Leave sync and watch notes empty by default instead of writing placeholder text.
- Preserve existing remote notes when moving or adopting files without --note.
- Detect tracked local moves by SHA-256 and update remote metadata safely.
- Skip files that vanish during watch scans instead of aborting the sync cycle.
- Bump NanoShare to 1.24.0 and the standalone CLI to 0.3.0.

routes/api/link.py

@@ -104,9 +104,10 @@ async def files_update(params, ctx):
     file_id=file_id,
     file_name=file_name,
     file_path=_safe_file_path(str(params.get('file_path') or '')),
-    note=params.get('note', ''),
+    note=params.get('note') if 'note' in params else None,
     expires_at=ensure_utc(parse_expires(params.get('expires', ''))),
     user_id=_user_id(ctx),
+    preserve_missing=True,
   )
   return {'updated': True}