Clickable menu entries

### Is your feature request related to a problem? Please describe.
At the bottom of the screen, lazygit shows the most popular actions fro the currently selected item. Those items are easy to trigger from the keyboard. And while the rest of the interface has ample support for clicking on stuff, that menu does not.

That does create some friction when introducing new users, because I cannot explain them to just click on stuff and expect that to work as an alternative to a shortcut key.

### Describe the solution you'd like
I would like those menu entries to be clickable to trigger their action.

### Describe alternatives you've considered
Use the keyboard.... Good for me, but not everyone likes it that way all the time. Especially for newbies, who have to read through the full thing anyway to understand how it works, I found, are sometimes better served by just clicking on stuff, until they are fluent using the TUI.