feat: add Selenium Settings page to configure paymentGroupId per office

Adds a new Settings → Advanced → Selenium Settings page where the office
name (paymentGroupId) used in United/DentalHub portal dropdowns can be
configured without touching code. Previously hardcoded as "Summit Dental
Care"; now injected from DB into the three United workers at job dispatch.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Backend/src/routes/insuranceStatusUnitedSCO.ts

@@ -3,6 +3,7 @@ import { storage } from "../storage";
 import { forwardOtpToSeleniumUnitedSCOAgent } from "../services/seleniumUnitedSCOEligibilityClient";
 import { io } from "../socket";
 import { enqueueSeleniumJob } from "../queue/jobRunner";
+import { prisma as db } from "@repo/db/client";
 
 const router = Router();
 
@@ -62,10 +63,13 @@ router.post(
         });
       }
 
+      const seleniumSettings = await db.seleniumSettings.findUnique({ where: { userId: req.user.id } });
+
       const enrichedData = {
         ...rawData,
         unitedscoUsername: credentials.username,
         unitedscoPassword: credentials.password,
+        paymentGroupId: seleniumSettings?.paymentGroupId ?? "",
       };
 
       const socketId: string | undefined = req.body.socketId;