Add CRUD methods for Kinosaal in HttpService

Introduced get, add, update, and delete methods for Kinosaal entities using a base API URL. Updated getAllKinosaal to return an array and refactored endpoints to use relative paths.

src/app/http.service.ts

@@ -6,12 +6,30 @@ import { Observable } from "rxjs";
 @Injectable({providedIn: 'root'})
 export class HttpService {
   private http = inject(HttpClient);
+  private baseUrl = '/api/';
 
-  getAllKinosaal(): Observable<Kinosaal> {
-    return this.http.get<Kinosaal>(`https://infinimotion.de/api/kinosaal`);
+  /* GET /api/kinosaal */
+  getAllKinosaal(): Observable<Kinosaal[]> {
+    return this.http.get<Kinosaal[]>(`${this.baseUrl}kinosaal`);
   }
 
+  /* GET /api/kinosaal/{id} */
+  getKinosaalById(id: number): Observable<Kinosaal> {
+    return this.http.get<Kinosaal>(`${this.baseUrl}kinosaal/${id}`);
+  }
+
+  /* POST /api/kinosaal */
   addKinosaal(kinosaal: Omit<Kinosaal, 'id'>): Observable<Kinosaal> {
-    return this.http.post<Kinosaal>(`https://infinimotion.de/api/kinosaal`, kinosaal);
+    return this.http.post<Kinosaal>(`${this.baseUrl}kinosaal`, kinosaal);
+  }
+
+  /* PUT /api/kinosaal/{id} */
+  updateKinosaal(id: number, kinosaal: Partial<Kinosaal>): Observable<Kinosaal> {
+    return this.http.put<Kinosaal>(`${this.baseUrl}kinosaal/${id}`, kinosaal);
+  }
+
+  /* DELETE /api/kinosaal/{id} */
+  deleteKinosaal(id: number): Observable<void> {
+    return this.http.delete<void>(`${this.baseUrl}kinosaal/${id}`);
   }
 }