feat: add multi_claim intent for different procedures per patient + fix batch claim PDF race

- Add multi_claim intent so AI correctly handles "claim X for patient A and Y for patient B"
  instead of applying all procedures to all patients (batch_claim)
- Each patient carries their own matchedCodes in the queue
- Fix batch claim PDF race condition: chatbot queue no longer advances in closeClaim(),
  instead advances after selenium PDF is downloaded (matching column claim behavior)
- Align United SCO eligibility worker with claim worker: only fill subscriber ID + DOB,
  use treatmentLocation by ID instead of arrow-wrapper click

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

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

@@ -47,6 +47,7 @@ export interface ChatResponse {
     | "eligibility_id_ready"
     | "batch_eligibility_ready"
     | "batch_claim_ready"
+    | "multi_claim_ready"
     | "batch_check_and_claim_ready"
     | "check_and_claim_ready"
     | "need_insurance_clarification"
@@ -345,6 +346,12 @@ export async function runInternalChatWorkflow(
     return await handleBatchClaim(classification, storage, customAliases);
   }
 
+  // ── Multi claim (different procedures for different patients) ─────────────
+
+  if (intent === "multi_claim") {
+    return await handleMultiClaim(classification, storage, customAliases);
+  }
+
   // ── Claim only (no eligibility check) ─────────────────────────────────────
 
   if (intent === "claim_only") {
@@ -810,6 +817,112 @@ async function handleBatchClaim(
   };
 }
 
+// ─── multi_claim (different procedures per patient) ─────────────────────────
+
+async function handleMultiClaim(
+  c: ChatClassification,
+  storage: StorageLike,
+  customAliases: { phrase: string; cdtCode: string }[]
+): Promise<ChatResponse> {
+  const groups = c.claimGroups ?? [];
+  if (groups.length < 2) {
+    if (groups.length === 1) {
+      return await handleClaimOnly(
+        { ...c, patientName: groups[0]!.patientName, procedureNames: groups[0]!.procedureNames, intent: "claim_only" },
+        storage,
+        customAliases
+      );
+    }
+    return { reply: "Please specify at least two patients with their procedures." };
+  }
+
+  const queue: {
+    patient: ResolvedPatient;
+    siteKey: string;
+    serviceDate: string | null;
+    appointmentId: number | null;
+    matchedCodes: { code: string; description: string; toothNumber?: string; toothSurface?: string; quad?: string }[];
+  }[] = [];
+  const notFound: string[] = [];
+
+  for (const group of groups) {
+    const name = group.patientName?.trim();
+    if (!name) continue;
+
+    const procedureNames = stripAttachmentRefs(group.procedureNames ?? []);
+    if (procedureNames.length === 0) continue;
+
+    const cdtResults: CdtResult[] = lookupCdtCodes(procedureNames, customAliases);
+    const matched = cdtResults.filter((r) => r.code !== null);
+    const unmatched = cdtResults.filter((r) => r.code === null);
+
+    if (unmatched.length > 0) {
+      const phrases = unmatched.map((r) => r.input);
+      return {
+        reply: `I don't recognize ${phrases.map((p) => `"${p}"`).join(", ")} for ${name}. What CDT code${phrases.length > 1 ? "s are" : " is"} ${phrases.length > 1 ? "they" : "it"}? (e.g. D0272)`,
+        action: "need_cdt_clarification",
+        actionData: { unknownPhrases: phrases, matchedSoFar: matched.map((r) => ({ code: r.code!, description: r.description })) },
+      };
+    }
+
+    const raw = await findPatientByName(name, storage);
+    if (!raw) {
+      notFound.push(name);
+      continue;
+    }
+    const patient = patientToResult(raw);
+    const fullName = `${patient.firstName ?? ""} ${patient.lastName ?? ""}`.trim();
+
+    const d1120Warning = checkD1120Age(matched, fullName, patient.dateOfBirth, c.appointmentDate);
+    if (d1120Warning) return d1120Warning;
+
+    const siteKey = resolveSiteKey(patient.insuranceProvider ?? null, c.insuranceHint ?? null) ?? "MH";
+
+    let serviceDate: string | null = c.appointmentDate ?? null;
+    if (!serviceDate) {
+      const now = new Date();
+      serviceDate = `${now.getFullYear()}-${String(now.getMonth() + 1).padStart(2, "0")}-${String(now.getDate()).padStart(2, "0")}`;
+    }
+
+    queue.push({
+      patient,
+      siteKey,
+      serviceDate,
+      appointmentId: null,
+      matchedCodes: matched.map((r) => ({ code: r.code!, description: r.description, toothNumber: r.toothNumber, toothSurface: r.toothSurface, quad: r.quad })),
+    });
+  }
+
+  if (notFound.length > 0 && queue.length === 0) {
+    return { reply: `Could not find any patients matching: ${notFound.join(", ")}. Please check the spelling.` };
+  }
+
+  const labels = queue.map((r) => {
+    const name = `${r.patient.firstName ?? ""} ${r.patient.lastName ?? ""}`.trim();
+    const codes = r.matchedCodes.map((c) => `${c.code}`).join(", ");
+    return `${name} (${codes})`;
+  });
+  let reply = `Ready to claim for ${queue.length} patients: ${labels.join("; ")}.`;
+  if (notFound.length > 0) {
+    reply += ` Could not find: ${notFound.join(", ")}.`;
+  }
+
+  return {
+    reply,
+    action: "multi_claim_ready",
+    actionData: {
+      queue: queue.map((r) => ({
+        patient: r.patient,
+        siteKey: r.siteKey,
+        serviceDate: r.serviceDate,
+        appointmentId: r.appointmentId,
+        matchedCodes: r.matchedCodes,
+      })),
+      renderingProvider: c.renderingProvider ?? null,
+    },
+  };
+}
+
 // ─── check_and_claim ─────────────────────────────────────────────────────────
 
 async function handleCheckAndClaim(