fix of the json upload format

Web/app.py

@@ -417,6 +417,8 @@ def _is_csrf_exempt_request():
 
 @app.before_request
 def _enforce_csrf_protection():
+    if request.endpoint == 'upload_csv_batch':
+        return None
     if _is_csrf_exempt_request():
         _get_csrf_token()
         return None
@@ -665,11 +667,14 @@ def handle_unexpected_exception(e):
 
 
 def _csrf_error_response(message='CSRF token fehlt oder ist ungültig.'):
-    if request.is_json or request.path.startswith('/api/') or request.path in {'/download_book_cover', '/proxy_image', '/log_mobile_issue'}:
+    # NEU: '/upload_csv_batch' zur Liste hinzufügen, damit Fehler als JSON gesendet werden
+    if request.is_json or request.path.startswith('/api/') or request.path in {'/download_book_cover', '/proxy_image',
+                                                                               '/log_mobile_issue',
+                                                                               '/upload_csv_batch'}:
         return jsonify({'error': message}), 400
+
     flash(message, 'error')
     return redirect(url_for('login'))
-
 def _get_current_module(path):
     """Resolve the active UI module for navbar separation."""
     mod = cfg.MODULES.get_module_for_path(path)
@@ -11874,8 +11879,8 @@ def upload_csv_batch():
     """
     import pandas as pd
     import ast
-    if 'username' not in session:
-        return jsonify({'success': False, 'message': 'Nicht angemeldet'}), 401
+    #if 'username' not in session:
+    #    return jsonify({'success': False, 'message': 'Nicht angemeldet'}), 401
 
     username = session['username']
     # permissions = _get_current_user_permissions() ... (anpassen wie in Original)