feat: persist AI conversation state in DB and fix LangGraph flow bugs

- Replace in-memory Maps in aiHandoffStore with DB-backed async functions
  using new patient_conversation table (stage + aiHandoff per patient)
- Add afterHoursEnabled to ai_settings table (persists across restarts)
- Fix runtime crash in reschedule-graph: mon/tue/wed variables were out
  of scope in the next-week fallback branch (ReferenceError)
- Wire rescheduleGreeting and generalFallback chat templates through to
  LangGraph nodes so user-configured messages take effect
- Add otherNode to reminder-graph to handle unclassified patient replies
  (e.g. "I want another appointment") and route to booking flow
- Fetch chatTemplates once per webhook request instead of per stage

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

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

@@ -15,7 +15,9 @@ import { ClaimListRelationFilterObjectSchema as ClaimListRelationFilterObjectSch
 import { PdfGroupListRelationFilterObjectSchema as PdfGroupListRelationFilterObjectSchema } from './PdfGroupListRelationFilter.schema';
 import { PaymentListRelationFilterObjectSchema as PaymentListRelationFilterObjectSchema } from './PaymentListRelationFilter.schema';
 import { CommunicationListRelationFilterObjectSchema as CommunicationListRelationFilterObjectSchema } from './CommunicationListRelationFilter.schema';
-import { PatientDocumentListRelationFilterObjectSchema as PatientDocumentListRelationFilterObjectSchema } from './PatientDocumentListRelationFilter.schema'
+import { PatientDocumentListRelationFilterObjectSchema as PatientDocumentListRelationFilterObjectSchema } from './PatientDocumentListRelationFilter.schema';
+import { PatientConversationNullableScalarRelationFilterObjectSchema as PatientConversationNullableScalarRelationFilterObjectSchema } from './PatientConversationNullableScalarRelationFilter.schema';
+import { PatientConversationWhereInputObjectSchema as PatientConversationWhereInputObjectSchema } from './PatientConversationWhereInput.schema'
 
 const patientwhereinputSchema = z.object({
   AND: z.union([z.lazy(() => PatientWhereInputObjectSchema), z.lazy(() => PatientWhereInputObjectSchema).array()]).optional(),
@@ -49,7 +51,8 @@ const patientwhereinputSchema = z.object({
   groups: z.lazy(() => PdfGroupListRelationFilterObjectSchema).optional(),
   payment: z.lazy(() => PaymentListRelationFilterObjectSchema).optional(),
   communications: z.lazy(() => CommunicationListRelationFilterObjectSchema).optional(),
-  documents: z.lazy(() => PatientDocumentListRelationFilterObjectSchema).optional()
+  documents: z.lazy(() => PatientDocumentListRelationFilterObjectSchema).optional(),
+  conversation: z.union([z.lazy(() => PatientConversationNullableScalarRelationFilterObjectSchema), z.lazy(() => PatientConversationWhereInputObjectSchema)]).optional()
 }).strict();
 export const PatientWhereInputObjectSchema: z.ZodType<Prisma.PatientWhereInput> = patientwhereinputSchema as unknown as z.ZodType<Prisma.PatientWhereInput>;
 export const PatientWhereInputObjectZodSchema = patientwhereinputSchema;