[feat] Allow the Window Menu to be modified within the frontend

[TechStudent10]

Describe the problem

I feel as if a lot of applications modify their menus dynamically. But you can only add the menu once, at the beginning of the application, in the backend. That means applications cannot change their menus, not in the backend nor the frontend.

Describe the solution you'd like

I would like a tauri-api function that allows you to change the menus. If not, at least in Tauri commands.

Alternatives considered

No response

Additional context

No response

[amrbashir]

duplicate of #6617