* Replace `RoomMember.Role.CREATOR` with `RoomMember.Role.Owner` - Make `RoomMember.Role` a sealed interface instead
* Adapt room member role mapping to include the power level to distinguish between admins and owners
* Use new `RoomMember.Role` sealed interface through the app
* Change how `MembersByRole` groups members to add owners to the admins section
* Adapt the `ChangeRoles` screen to the new roles:
- Owners can't modify other owner's roles.
- They can modify the roles of any other user, without confirmation.
* Adapt 'roles and permissions' screen:
- Owners can't demote themselves.
- The admin count also counts owners.
* Add more tests and screenshots
* Add owners to its own section in the 'change roles' screen
* Update screenshots
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Co-authored-by: ElementBot <android@element.io>