[Proposal] Toggle help instead of showing help

[saona-raimundo]

Hi! Thanks for the crate!

I just tried and wanted to suggest a UI behaviour.

Current behaviour

Help message (or the help tab) is shown with keys H or F1.
When going from a search to the help message, I tried to go back to the search by pressing H again, or Esc, but did not work.
The current solution is to press F, as stated in the help message and in the tabs.

Proposal

The proposal is to change the help behaviour from showing to toggling the help screen.
To go out of the help screen, one may go to the file search if there is any, or to the new scan otherwise.

Options

Introduce Esc special behaviour while in the help screen.

[funbiscuit]

Thanks for the suggestion!
I think the same should be done for logs tab of the app.
Currently it can be done kind of awkwardly so I'll implement this after some refactoring of app.rs