* Move `ChangeRoles*` classes to their own module so they can be shared
* Hook the change roles screen to the leave room action, add confirmation dialogs
* Use enum instead of sealed interface for `ChangeRoomMemberRolesListType`
* Try to improve communications between nodes
* refactor (leave room) : makes sure to expose only necessary code from api module
* Add `:libraries:previewutils` module to share some test fixtures used for UI previews
* Update screenshots
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Co-authored-by: ElementBot <android@element.io>
Co-authored-by: ganfra <francoisg@matrix.org>
