ci: check "Show more" while its page loads in the smoke test

With the test directory stopped, the next "ci avatar" page waits 10 s before it fails. The smoke test taps "Show more" then, takes a screenshot that shows its colour, and requires it to be disabled. The smoke step gets BACKEND_DIR, so the ui helper can stop and start the directory. One layout only: the row's colour and state are the same in both.

.github/workflows/ios-sim.yml

@@ -265,6 +265,8 @@ jobs:
         run: brew install cameroncooke/axe/axe
 
       - name: Run smoke test
+        env:
+          BACKEND_DIR: ${{ runner.temp }}/backend
         run: scripts/ci/ios-sim/smoke-test.sh "$RUNNER_TEMP/DerivedData/Build/Products/Debug-iphonesimulator/SimpleX.app" "$RUNNER_TEMP/smoke-test"
 
       - name: Install Claude Code