feat: add license activation system with feature gates

- License key generator tool at ~/Desktop/LicenseGenerator
- Backend validator route (GET /api/license/status, POST /api/license/activate)
- Activation page in sidebar with status, key input, and free/premium feature list
- useLicense hook for frontend license state
- Feature gates: premium eligibility buttons (DDMA, DeltaIns, Tufts, United, CCA) disabled without license
- Feature gates: premium claim buttons (CCA, Delta MA, United, Tufts) and all PreAuth buttons disabled without license
- Free features always active: MassHealth eligibility/claim, Documents, Payments, Backups, Reports
- README: license key generator usage instructions

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

apps/Frontend/src/pages/claims-page.tsx

@@ -34,6 +34,7 @@ import ClaimDocumentsUploadMultiple from "@/components/claims/claim-document-upl
 import { QK_PATIENTS_BASE } from "@/components/patients/patient-table";
 import { PdfPreviewModal } from "@/components/insurance-status/pdf-preview-modal";
 import { socket } from "@/lib/socket";
+import { useLicense } from "@/hooks/use-license";
 
 export default function ClaimsPage() {
   const [isClaimFormOpen, setIsClaimFormOpen] = useState(false);
@@ -52,6 +53,7 @@ export default function ClaimsPage() {
   const { status, message, show } = useAppSelector(
     (state) => state.seleniumTasks.claimSubmit
   );
+  const { isLicensed } = useLicense();
 
   // Track pending selenium jobs so we can react to completion via socket
   const [pendingClaimJobId, setPendingClaimJobId] = useState<string | null>(null);
@@ -911,6 +913,7 @@ export default function ClaimsPage() {
           onHandleForDDMASeleniumClaim={handleDDMAClaimSubmitSelenium}
           onHandleForUnitedDHSeleniumClaim={handleUnitedDHClaimSubmitSelenium}
           onHandleForTuftsSCOSeleniumClaim={handleTuftsSCOClaimSubmitSelenium}
+          isLicensed={isLicensed}
         />
       )}