v1.4.5

bump version to 1.4.5 and improve hotkey handling in window events

- Updated package version in Cargo.toml and tauri.conf.json to 1.4.5.
- Refactored hotkey handling logic in window_events.rs to improve responsiveness:
  - Unregister hotkeys immediately to prevent keyboard lock-up.
  - Use a flag to determine whether to hide the window based on hotkey usage.