Description

Currently, when PearPass is closed, the application terminates completely. This breaks the connection with the browser extension, forcing users to either reopen the native app manually or even re-pair the extension from scratch. Since a password manager needs to maintain a stable connection with the browser, it should be able to run silently in the background.

Proposed Solution

Add an optional setting (disabled by default to preserve current behavior) that allows the app to run in the background when the main window is closed:

1. Intercept the window close event and call window.hide() instead of terminating the process.
2. Keep the app alive via the system tray (menu bar / system tray icon) so the connection with the browser extension remains active.
3. OS Specifics: On macOS, additionally call app.dock.hide() when hidden (and app.dock.show() when restored) to completely remove the icon from the Dock bar while running in the background.
4. Add a "Quit" option to the tray context menu to allow completely closing the app when needed.