Remove SessionData.needsVerification as the source of truth for session verification status (#2748)

* Remove `SessionData.needsVerification` as the source of truth for session verification status.

- Use the Rust SDK `EncryptionService.verificationState()` instead, but always waiting for the first 'known' result (either verified or not, discarding 'unknown').
- Add a workaround in the super rare case when reading this value gets stuck somehow. We'll assume the user is not verified in that case.
- Make `DefaultFtueService.getNextStep` and dependent checks `suspend`.
- Make the `skip` button use a value in the session preferences instead.

* Log exception when the verification status can't be loaded

Co-authored-by: Benoit Marty <benoit@matrix.org>

* Fix review comments

---------

Co-authored-by: Benoit Marty <benoit@matrix.org>

features/signedout/impl/src/main/kotlin/io/element/android/features/signedout/impl/SignedOutStateProvider.kt

@@ -38,7 +38,6 @@ fun aSignedOutState() = SignedOutState(
 fun aSessionData(
     sessionId: SessionId = SessionId("@alice:server.org"),
     isTokenValid: Boolean = false,
-    needsVerification: Boolean = false,
 ): SessionData {
     return SessionData(
         userId = sessionId.value,
@@ -52,6 +51,5 @@ fun aSessionData(
         isTokenValid = isTokenValid,
         loginType = LoginType.UNKNOWN,
         passphrase = null,
-        needsVerification = needsVerification,
     )
 }