v0.4.5

Release v0.4.5

- **Auto-update mechanism improvements**
  - Add binary file modification time tracking for reliable restart detection
  - Add write permission pre-check before attempting updates
  - Add Windows-specific error message (Windows doesn't support in-place updates)
  - Improve all error messages with manual update instructions and GitHub release links

- **Update state management**
  - Add `restartPending` field to `/admin/api/update/check` API
  - Remove frontend state dependency (`updatedVersion` variable)
  - Use backend state based on file system metadata
  - Fix state persistence issue across page refreshes
  - Work reliably in container environments without temporary files

- Fix issue where update state was lost on page refresh
- Fix issue where error recovery didn't log restore failures
- Add proper error handling for permission issues and cross-device scenarios