Fix ci.yml: restore desktop-smoke job header

The previous commit's edit consumed the desktop-smoke job header when
inserting e2e-local, leaving its body orphaned with a duplicate steps key.
GitHub rejected the workflow on startup. Restore the header.

Author: RhysSullivan

.github/workflows/ci.yml

@@ -100,6 +100,10 @@ jobs:
       - name: Run local e2e scenarios
         run: bun run test:local
         working-directory: e2e
+
+  desktop-smoke:
+    name: Desktop smoke build
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4