feat: Close neovim if neominimap is the last window on WinClosed event

[DriesOlbrechts]

When using the split layout, neovim doesn't fully close until you also close the neominimap window. This PR fixes that.

This might not be wanted behavior for you, so feel free to just close this or suggest improvements.

[Isrothy]

Thank you for your contribution and effort in making this pull request!

Before we can merge it, there are a couple of things I’d like to address:

• Optional Feature: I believe this feature should be optional to allow users to choose whether or not they want to enable it.
• Condition for Last Window: The current condition to check if the minimap is the last window isn’t correct. This could lead to unintended behavior.
• quitall closes all tabs, but I believe the user only want to close the tab where minimap is the last window.

I have addressed these issues in a separate PR #132. Please feel free to check it out and let me know your thoughts! Your feedback is highly valued, and I'm open to further discussion.