feat: add PreAuth tab, preauth selenium flow, and PreAuth No column

- Insurance Forms modal: split into Insurance Claim / PreAuth tabs
- PreAuth tab: same patient info + service lines, no toggle/direct combos
- Excluded Recalls & New Patients, Composite Fillings (Front/Back), Pedo from PreAuth combos
- Extractions: replaced Simple/Surg/Baby Teeth EXT with Full Bony EXT (D7240)
- MH PreAuth button: rewritten selenium worker to use masshealth-dental.org,
  selects Dental Prior Authorization (2nd option), skips Date of Service field
- agent.py: convert pdf_path to pdf_url for /claim-pre-auth endpoint
- nginx + Express: raise body size limit to 50mb (fix 413 errors)
- DB schema: appointmentId optional on Claim, add preAuthNumber field, add PREAUTH status
- Backend: create PREAUTH claim record on preauth submit, save preAuthNumber on completion
- Claims table: add PreAuth No column (blue) next to Claim No

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

apps/Frontend/src/components/claims/claims-recent-table.tsx

@@ -311,6 +311,7 @@ export default function ClaimsRecentTable({
               {allowCheckbox && <TableHead>Select</TableHead>}
               <TableHead>Claim ID</TableHead>
               <TableHead>Claim No</TableHead>
+              <TableHead>PreAuth No</TableHead>
               <TableHead>Patient Name</TableHead>
               <TableHead>Submission Date</TableHead>
               <TableHead>Insurance Provider</TableHead>
@@ -371,6 +372,11 @@ export default function ClaimsRecentTable({
                       {claim.claimNumber ?? "—"}
                     </div>
                   </TableCell>
+                  <TableCell>
+                    <div className="text-sm font-medium text-blue-700">
+                      {(claim as any).preAuthNumber ?? "—"}
+                    </div>
+                  </TableCell>
                   <TableCell>
                     <div className="flex items-center">
                       <Avatar