fix(desktop): fix sqlite disconnect warning issue

[ysfscream]

PR Checklist

If you have any questions, you can refer to the Contributing Guide

What is the current behavior?

When closing the application, an unhandled promise rejection occurs with error: SQLITE_MISUSE: Database handle is closed. This happens because the application attempts to close the database connection multiple times during the shutdown process, causing errors when trying to close an already closed connection.

Issue Number

What is the new behavior?

Added safeguards to prevent multiple database connection close attempts:

1. Added a flag to track if connections have already been destroyed
2. Enhanced the connection destroy function with proper error handling
3. Modified app shutdown flow to avoid duplicate cleanup calls
4. Improved error handling in database connection management

This prevents the unhandled promise rejection and ensures a clean application shutdown.

Does this PR introduce a breaking change?

• Yes
• No

Specific Instructions

No special instructions needed. This fix addresses the database connection closure error without changing any application functionality.

Other information

The error occurred because both the window's close event handler and the app's window-all-closed event handler were attempting to close database connections, leading to the same connection being closed twice.