Floating Action Button for search function

[skyGtm]

Checklist

• [x] I checked, but didn't find any duplicates (open OR closed) of this issue in the repo.
• [x] I have read the contribution guidelines given at https://github.com/TeamNewPipe/NewPipe/blob/HEAD/.github/CONTRIBUTING.md.
• [x] This issue contains only one feature request. I will open one issue for every feature I want to request.

Describe the feature you want

Floating action button for search functionality at the bottom of the main page and search results page (and other places as required). and (may be) ability to disable it from the settings (for people who don't require it)

Is your feature request related to a problem? Please describe it

As the devices are becoming longer, it is difficult to reach search icon at the top of the screen while using the app with one hand.

Additional context

How will you/everyone benefit from this feature?

People, who own bigger devices, don't have to stretch their finger to reach to search button.