test(portal): expect /learn static route in delivery order

Align static delivery route inventory with the learn standalone pages mount
so fast-release guard tests pass on feature/learn-standalone-pages.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/portal-static-delivery-routes.test.mjs

@@ -181,6 +181,7 @@ test('registers static delivery routes and middleware in legacy order', () => {
       ['use', '/plaza-covers'],
       ['use', '/brand'],
       ['use', '/assets'],
+      ['use', '/learn'],
       ['get', '/dev/wechat-share-preview'],
       ['use', '/dev'],
       [
@@ -206,6 +207,10 @@ test('registers static delivery routes and middleware in legacy order', () => {
       '/project/public/assets',
       { maxAge: '1d' },
     ],
+    [
+      '/project/public/learn',
+      { maxAge: '5m', index: 'index.html' },
+    ],
     ['/project/public/dev', { maxAge: 0 }],
     [
       '/project/dist',