Rename the custom recovery passphrase well-known to match the merged schema

The merged element-enterprise#261 well-known schema advertises the feature
under custom_recovery_passphrase (no _settings/_requirements suffix), so the
parser previously looking for custom_recovery_passphrase_settings would never
activate the flow. Update the @SerialName and drop the narrow "Requirements"
suffix from the type — the block is now general, extensible feature settings —
to mirror the .pkl CustomRecoveryPassphrase class. Bumps the enterprise
submodule to the matching consumer change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

libraries/wellknown/test/src/main/kotlin/io/element/android/features/wellknown/test/Fixtures.kt

@@ -8,7 +8,7 @@
 
 package io.element.android.features.wellknown.test
 
-import io.element.android.libraries.wellknown.api.CustomRecoveryPassphraseRequirements
+import io.element.android.libraries.wellknown.api.CustomRecoveryPassphrase
 import io.element.android.libraries.wellknown.api.ElementWellKnown
 
 fun anElementWellKnown(
@@ -18,7 +18,7 @@ fun anElementWellKnown(
     brandColor: String? = null,
     notificationSound: String? = null,
     identityProviderAppScheme: String? = null,
-    customRecoveryPassphraseRequirements: CustomRecoveryPassphraseRequirements? = null,
+    customRecoveryPassphrase: CustomRecoveryPassphrase? = null,
 ) = ElementWellKnown(
     registrationHelperUrl = registrationHelperUrl,
     enforceElementPro = enforceElementPro,
@@ -26,11 +26,11 @@ fun anElementWellKnown(
     brandColor = brandColor,
     notificationSound = notificationSound,
     identityProviderAppScheme = identityProviderAppScheme,
-    customRecoveryPassphraseRequirements = customRecoveryPassphraseRequirements,
+    customRecoveryPassphrase = customRecoveryPassphrase,
 )
 
-fun aCustomRecoveryPassphraseRequirements(
+fun aCustomRecoveryPassphrase(
     minCharacterCount: Int = 8,
-) = CustomRecoveryPassphraseRequirements(
+) = CustomRecoveryPassphrase(
     minCharacterCount = minCharacterCount,
 )