Add special flow for leaving a space as the last owner (#6112)

* When the user is in a v12 room, use different UI to select the last owner when leaving

- Add `LeaveSpaceRoom.areCreatorsPrivileged` to detect when this is happening.
- Import new strings.
- Build the new UI.
- Attach it to a change member roles screen navigation.

* Don't display the `isLastOwner` UI if the user is the only joined one in the room

* Rename `LeaveSpaceState.isLastOwner` to `.needsOwnerChange`. This way, it's easier to understand the difference with the passed `LeaveSpaceRoom.isLastOwner` value

* Add a test for the new check of user not being the last joined member

* Fix paddings in `LeaveSpaceView`

* Update screenshots

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Co-authored-by: ElementBot <android@element.io>

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/spaces/LeaveSpaceRoom.kt

@@ -11,4 +11,5 @@ package io.element.android.libraries.matrix.api.spaces
 data class LeaveSpaceRoom(
     val spaceRoom: SpaceRoom,
     val isLastOwner: Boolean,
+    val areCreatorsPrivileged: Boolean,
 )