ci: run smoke tests after build

[jonathanlab]

We were not running E2E tests on the release artifacts, making it possible to release a build that would not boot at all.

This is the same E2E test we run during the build step on a PR, but during release. See #2385 and #2433 for a scenario where CI passed, but the release would still not boot.

[greptile-apps]

Prompt To Fix All With AI

Fix the following 1 code review issue. Work through them one at a time, proposing concise fixes.

---

### Issue 1 of 1
.github/workflows/code-release.yml:143-144
The `playwright install --with-deps chromium` step downloads a Chromium browser binary (~150 MB) that is never used. The smoke tests launch the packaged Electron app directly via `_electron.launch({ executablePath: appPath })`, so Playwright's own Chromium runtime is not involved. On macOS the `--with-deps` flag also does not install meaningful system packages (unlike Linux). This adds unnecessary time and bandwidth to every release run.

```suggestion
      - name: Install Playwright
        run: pnpm --filter code exec playwright install
```

_{Reviews (1): Last reviewed commit: "ci: run smoke tests after build" | Re-trigger Greptile}