KI-AGENT: Leere JSON Requests in der Mobile App korrigieren

mobile/src/lib/api.ts

@@ -313,14 +313,15 @@ async function parseJson(response: Response): Promise<unknown> {
 }
 
 export async function apiRequest<T>(path: string, options: RequestOptions = {}): Promise<T> {
+  const hasJsonBody = options.body !== undefined;
   const response = await fetch(buildUrl(path), {
     method: options.method || 'GET',
     headers: {
       Accept: 'application/json',
-      'Content-Type': 'application/json',
+      ...(hasJsonBody ? { 'Content-Type': 'application/json' } : {}),
       ...(options.token ? { Authorization: `Bearer ${options.token}` } : {}),
     },
-    body: options.body ? JSON.stringify(options.body) : undefined,
+    body: hasJsonBody ? JSON.stringify(options.body) : undefined,
   });
 
   const payload = await parseJson(response);