fix: allow claims without appointment + support post/core multi-tooth input

- Make appointmentId nullable/optional in Prisma Zod schema via @zod rich
  comment so claims can be submitted without an existing appointment
- Convert undefined appointmentId to null in all claim form handlers and
  the backend claim creation endpoint
- Add AI classifier rule for expanding one procedure across multiple
  comma-separated tooth numbers (e.g. "post/core on #23, 24, 25, 26")
- Add "post/core" (slash) alias to CDT lookup maps

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

packages/db/shared/schemas/variants/result/Claim.result.ts

@@ -5,7 +5,7 @@ import { ClaimStatusSchema } from '../../enums/ClaimStatus.schema';
 export const ClaimResultSchema = z.object({
     id: z.number().int(),
     patientId: z.number().int(),
-    appointmentId: z.number().int().nullable(),
+    appointmentId: z.number().int().int().nullable(),
     userId: z.number().int(),
     staffId: z.number().int(),
     patientName: z.string(),