Close app when lock database by button

### Checks

- [x] I have read the Wiki, searched the open issues, and still think this is a new feature.

### Explain the problem clearly and succinctly:

Please, add option to close application when database is closed by close button. I mean that typical use of application is: run applicatio - open database - search password - lock and close app (ideally in one step).

### Describe the solution you'd like:

Add app option "when database is locked then close app".

### Describe alternatives you've considered:

_No response_

### Additional context:

_No response_

Start by tracing the database close-button flow and locating the application settings that control lock behavior. The work is done when users can enable an option that closes the application after locking the database, while the existing behavior remains unchanged when it is disabled.

Written by the indexing model from the issue text.