Key backup Rust API adoption (#1952)

* Adopt Rust side secure backup APIs (incomplete, based on poljar/backup-pr)

* Implement the home screen recovery key confirmation banner.

* Update with the latest Rust changes.

The loading button for .unknown was incorrect. It should be treated as disabled.

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Co-authored-by: Doug <douglase@element.io>

ElementX/Sources/Screens/HomeScreen/HomeScreenCoordinator.swift

@@ -32,6 +32,7 @@ enum HomeScreenCoordinatorAction {
     case presentSettingsScreen
     case presentFeedbackScreen
     case presentSessionVerificationScreen
+    case presentSecureBackupSettings
     case presentStartChatScreen
     case presentInvitesScreen
     case logout
@@ -75,6 +76,8 @@ final class HomeScreenCoordinator: CoordinatorProtocol {
                     actionsSubject.send(.presentSettingsScreen)
                 case .presentSessionVerificationScreen:
                     actionsSubject.send(.presentSessionVerificationScreen)
+                case .presentSecureBackupSettings:
+                    actionsSubject.send(.presentSecureBackupSettings)
                 case .logout:
                     actionsSubject.send(.logout)
                 case .presentStartChatScreen: