[AAE-10103] language-menu storybook (#7732)

lib/core/services/language.service.interface.ts

@@ -0,0 +1,26 @@
+/*!
+ * @license
+ * Copyright 2022 Alfresco Software, Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Observable } from 'rxjs';
+import { LanguageItem } from './language-item.interface';
+
+export interface LanguageServiceInterface {
+
+    languages$: Observable<LanguageItem[]>;
+    changeLanguage(language: LanguageItem): void;
+    setLanguages(items: LanguageItem[]): void;
+}