fix(portal): prefix unused totalPending param with underscore

Silence @typescript-eslint/no-unused-vars for totalPending in
PaymentModal — it is accepted as a prop for API compatibility but the
modal computes selectedTotal from selected invoices instead.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

package.json

@@ -17,5 +17,6 @@
     "node": ">=20",
     "pnpm": ">=9"
   },
-  "packageManager": "pnpm@9.15.4"
+  "packageManager": "pnpm@9.15.4",
+  "license": "AGPL-3.0-only"
 }