* feat(conference/native): update indicator styles

* feat(prejoin/native): removed unnecessary styles

* feat(mobile/navigation): fixed header buttons style

* feat(mobile/navigation): fixed linter

* feat(base/modal): order props alphabetically

* feat(base/ui): added ripple color for tertiary button

* feat(prejoin): removed autoFocus from input and adjusted content

* feat(conference): adjusted RaisedHandCountLabel and added extra code spaces

* feat(prejoin): fixed content to fit tablets

* feat(conference): moved header button styles to navigation styles

* feat(mobile/navigation): updated header navigation button styles

* feat(prejoin): updated elements width, removed left inset

* feat(mobile/navigation): replaced native stack with stack navigator and other ui fixes

Skip the welcome page for now, until we can remove the audio / video
toggle.

Introduce navigation for all in-conference screens.