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/AiSettingsScalarWhereWithAggregatesInput.schema.ts

@@ -1,7 +1,8 @@
 import * as z from 'zod';
 import type { Prisma } from '../../../generated/prisma';
 import { IntWithAggregatesFilterObjectSchema as IntWithAggregatesFilterObjectSchema } from './IntWithAggregatesFilter.schema';
-import { StringWithAggregatesFilterObjectSchema as StringWithAggregatesFilterObjectSchema } from './StringWithAggregatesFilter.schema'
+import { StringWithAggregatesFilterObjectSchema as StringWithAggregatesFilterObjectSchema } from './StringWithAggregatesFilter.schema';
+import { BoolWithAggregatesFilterObjectSchema as BoolWithAggregatesFilterObjectSchema } from './BoolWithAggregatesFilter.schema'
 
 const aisettingsscalarwherewithaggregatesinputSchema = z.object({
   AND: z.union([z.lazy(() => AiSettingsScalarWhereWithAggregatesInputObjectSchema), z.lazy(() => AiSettingsScalarWhereWithAggregatesInputObjectSchema).array()]).optional(),
@@ -9,7 +10,8 @@ const aisettingsscalarwherewithaggregatesinputSchema = z.object({
   NOT: z.union([z.lazy(() => AiSettingsScalarWhereWithAggregatesInputObjectSchema), z.lazy(() => AiSettingsScalarWhereWithAggregatesInputObjectSchema).array()]).optional(),
   id: z.union([z.lazy(() => IntWithAggregatesFilterObjectSchema), z.number().int()]).optional(),
   userId: z.union([z.lazy(() => IntWithAggregatesFilterObjectSchema), z.number().int()]).optional(),
-  apiKey: z.union([z.lazy(() => StringWithAggregatesFilterObjectSchema), z.string()]).optional()
+  apiKey: z.union([z.lazy(() => StringWithAggregatesFilterObjectSchema), z.string()]).optional(),
+  afterHoursEnabled: z.union([z.lazy(() => BoolWithAggregatesFilterObjectSchema), z.boolean()]).optional()
 }).strict();
 export const AiSettingsScalarWhereWithAggregatesInputObjectSchema: z.ZodType<Prisma.AiSettingsScalarWhereWithAggregatesInput> = aisettingsscalarwherewithaggregatesinputSchema as unknown as z.ZodType<Prisma.AiSettingsScalarWhereWithAggregatesInput>;
 export const AiSettingsScalarWhereWithAggregatesInputObjectZodSchema = aisettingsscalarwherewithaggregatesinputSchema;