TF-3189 new option to enable/disable subaddressing for a personal folder

lib/features/mailbox/domain/exceptions/null_session_or_accountid_exception.dart

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+
+class NullSessionOrAccountIdException implements Exception {
+
+  NullSessionOrAccountIdException();
+
+  @override
+  String toString() => 'NullSessionOrAccountIdException: session and accountId should not be null';
+}

lib/features/mailbox/domain/exceptions/set_mailbox_rights_exception.dart

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+
+class SetMailboxRightsException implements Exception {
+
+  SetMailboxRightsException();
+
+  @override
+  String toString() => 'Failed to update mailbox rights.';
+}