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>

apps/web/eslint.config.js

@@ -1,6 +1,13 @@
 import tseslint from "typescript-eslint";
 
 export default tseslint.config(
+  {
+    ignores: [
+      // Untracked .js files containing JSX (build artifacts)
+      "src/**/*.js",
+      "src/**/*.jsx",
+    ],
+  },
   ...tseslint.configs.recommended,
   {
     rules: {