Floating toolbar (#6147)
* Use floating toolbar on homepage
* Fix deprecation issue
* Create HorizontalFloatingToolbar wrapper in our components.
* Fix Konsist test.
* Fix compilation issue after rebase.
* Fix lint issue. `floatingActionButton` must be the last parameter.
* Add Preview for the case empty space.
* Fix navigation bar overlapping buttons in empty space view.
* Increase content padding, and apply it to the space tab too.
* Update screenshots
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Co-authored-by: chelsea <git@cdhildit.ch>
Co-authored-by: ElementBot <android@element.io>
