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>

apps/Backend/src/ai/cdt-lookup.ts

@@ -105,6 +105,7 @@ const ALIAS_MAP: Record<string, string> = {
   "recement":              "re-cement",
   "post core":             "post and core",
   "post and core":         "post and core",
+  "post/core":             "post and core",
   // Root canal (endodontic)
   "root canal":            "endodontic therapy",
   "rct":                   "endodontic therapy",
@@ -178,6 +179,7 @@ const DIRECT_CODE_MAP: Record<string, string> = {
   "post":                   "D2954",
   "pos":                    "D2954",
   "post core":              "D2954",
+  "post/core":              "D2954",
   // Crowns
   "recement":               "D2920",
   "re cement":              "D2920",

apps/Backend/src/ai/internal-chat-graph.ts

@@ -152,6 +152,12 @@ Rules:
   e.g. "#20 rct, post, crown" → ["#20 rct", "#20 post", "#20 crown"]
   e.g. "preauth #20 rct, pos, crown" → ["#20 rct", "#20 pos", "#20 crown"]
   e.g. "#14 rct, buildup, crown" → ["#14 rct", "#14 buildup", "#14 crown"]
+- When a procedure is followed by MULTIPLE tooth numbers (comma-separated, with or without # on each), apply the procedure to EVERY tooth number as separate entries.
+  e.g. "post/core on #23, 24, 25, 26" → ["post/core #23", "post/core #24", "post/core #25", "post/core #26"]
+  e.g. "crown #3, #5, #12" → ["crown #3", "crown #5", "crown #12"]
+  e.g. "extraction #1, 16, 17, 32" → ["extraction #1", "extraction #16", "extraction #17", "extraction #32"]
+  e.g. "rct #23, 24, 25" → ["rct #23", "rct #24", "rct #25"]
+  "post/core" is the same as "post core" — a combined post and core procedure
 - For RCT/root canal with a tooth number, preserve the tooth# in the entry:
   e.g. "rct #29", "#14 root canal", "rct #6", "#20 rct" — keep the #number with the procedure so the correct code can be selected
 - For a CDT code (D####) followed by a tooth number (# NN or #NN), keep them together as ONE entry and do NOT spread the tooth# to other procedures:

apps/Backend/src/routes/claims.ts

@@ -1152,7 +1152,7 @@ router.post("/", async (req: Request, res: Response): Promise<any> => {
     // Strip unknown keys so strict() doesn't reject any extra properties the frontend may send
     const parsedClaim = (ExtendedClaimSchema as unknown as z.ZodObject<any>).strip().parse({
       patientId: req.body.patientId,
-      appointmentId: req.body.appointmentId,
+      appointmentId: req.body.appointmentId ?? null,
       staffId: req.body.staffId,
       patientName: req.body.patientName,
       memberId: req.body.memberId,