fix(scheduler): use equals: null filter for endDate to satisfy Prisma where syntax and stop log spam

backend/src/app.js

@@ -87,6 +87,11 @@ if (securityConfig.csrf.enabled) {
     }
     next(err);
   });
+} else {
+  // Provide a harmless CSRF endpoint in development when CSRF is disabled
+  app.get('/api/csrf-token', (req, res) => {
+    res.json({ csrfToken: null, disabled: true });
+  });
 }
 
 // Request logging middleware