feat: office address, multi-template SMS manager, hardcoded defaults with auto-seed

- Add streetAddress/city/state/zipCode fields to OfficeContact (schema + storage + UI)
- Support {officeAddress} variable in batch reminder SMS
- Replace single SMS template field with full CRUD template list (add/rename/edit/delete)
- Store SMS template list under _sms_template_list; first template synced to batch reminder
- Hardcode all AI chat template defaults into codebase (reminder SMS, greetings, fallback)
- Add seed-templates.ts that auto-seeds default templates for all users on server boot
- Update README: note that templates are auto-configured on first boot

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

packages/db/prisma/schema.prisma

@@ -605,6 +605,10 @@ model OfficeContact {
   phoneNumber      String?
   email            String?
   fax              String?
+  streetAddress    String?
+  city             String?
+  state            String?
+  zipCode          String?
 
   user User @relation(fields: [userId], references: [id], onDelete: Cascade)