Move session verification to FTUE flow, make it mandatory (#2594)

* Move session verification to the FTUE
* Allow session verification flow to be restarted
* Use `EncryptionService` to display session verification faster
* Remove session verification item from settings
* Remove session verification banner from room list
* Remove 'verification needed' variant from the `TimelineEncryptedHistoryBanner`
* Improve verification flow UI and UX
* Remove 'verification successful' snackbar message
* Only register push provider after the session has been verified
* Hide room list while the session hasn't been verified
* Prevent deep links from changing the navigation if the session isn't verified
* Update screenshots
* Renamed `FtueState` to `FtueService`, created an actual `FtueState`.

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Co-authored-by: ElementBot <benoitm+elementbot@element.io>

samples/minimal/src/main/kotlin/io/element/android/samples/minimal/RoomListScreen.kt

@@ -152,7 +152,6 @@ class RoomListScreen(
             state = state,
             onRoomClicked = ::onRoomClicked,
             onSettingsClicked = {},
-            onVerifyClicked = {},
             onConfirmRecoveryKeyClicked = {},
             onCreateRoomClicked = {},
             onInvitesClicked = {},