Prevent Multiple Instances of the Application

[Zingzy]

The application currently allows multiple instances to run simultaneously, which can lead to unexpected behavior and resource conflicts. We need to implement a mechanism to prevent multiple instances of the application from running at the same time.

Tasks:

• Research methods to detect and prevent multiple instances of the application.
• Implement a mechanism to check for existing instances at startup.
• Display a user-friendly message if another instance is already running.
• Write unit tests to verify the functionality of the instance prevention mechanism.
• Update the documentation to reflect the changes in the application's startup behavior.

Additional Context: Preventing multiple instances can be achieved using various methods, such as creating a lock file, using inter-process communication (IPC), or leveraging platform-specific APIs. The chosen method should be reliable and cross-platform if possible