feat: AI chat system with LangGraph, multi-step patient flows, and appointment rescheduling

- Add floating chat window Hand-off to AI toggle (per-patient) and after-hours AI toggle (global)
- Add LangGraph-powered appointment reminder flow: AI introduces itself, classifies YES/NO, handles confirmation with appointment date/time
- Add multi-step rescheduling flow: ASAP vs next week, tomorrow offer, Mon/Tue/Wed picker, morning/afternoon time slot — automatically updates appointment in DB
- Add new patient / after-hours flow: new vs existing patient, dental insurance check, MassHealth Selenium eligibility check (auto-uses saved member ID + DOB for existing patients), self-pay fallback
- Add AI Chat Settings page (Settings → Advanced) with editable greeting templates and LangGraph flow diagrams for both reminder and new-patient flows
- Add Schedule a New Patient template option in chat window, starts new-patient conversation flow
- Add GET/PUT endpoints for AI handoff, after-hours handoff, and AI chat templates
- Add multilingual support (7 languages) across all AI reply nodes with LLM generation and hardcoded fallbacks
- Add pending reschedule in-memory store and conversation stage tracking across all flows

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

packages/db/shared/schemas/objects/UserSelect.schema.ts

@@ -18,6 +18,7 @@ import { AiSettingsArgsObjectSchema as AiSettingsArgsObjectSchema } from './AiSe
 import { OfficeHoursArgsObjectSchema as OfficeHoursArgsObjectSchema } from './OfficeHoursArgs.schema';
 import { OfficeContactArgsObjectSchema as OfficeContactArgsObjectSchema } from './OfficeContactArgs.schema';
 import { ProcedureTimeslotArgsObjectSchema as ProcedureTimeslotArgsObjectSchema } from './ProcedureTimeslotArgs.schema';
+import { InsuranceContactFindManySchema as InsuranceContactFindManySchema } from '../findManyInsuranceContact.schema';
 import { UserCountOutputTypeArgsObjectSchema as UserCountOutputTypeArgsObjectSchema } from './UserCountOutputTypeArgs.schema'
 
 const makeSchema = () => z.object({
@@ -44,6 +45,7 @@ const makeSchema = () => z.object({
   officeHours: z.union([z.boolean(), z.lazy(() => OfficeHoursArgsObjectSchema)]).optional(),
   officeContact: z.union([z.boolean(), z.lazy(() => OfficeContactArgsObjectSchema)]).optional(),
   procedureTimeslot: z.union([z.boolean(), z.lazy(() => ProcedureTimeslotArgsObjectSchema)]).optional(),
+  insuranceContacts: z.union([z.boolean(), z.lazy(() => InsuranceContactFindManySchema)]).optional(),
   _count: z.union([z.boolean(), z.lazy(() => UserCountOutputTypeArgsObjectSchema)]).optional()
 }).strict();
 export const UserSelectObjectSchema: z.ZodType<Prisma.UserSelect> = makeSchema() as unknown as z.ZodType<Prisma.UserSelect>;