Implements a standalone smoke test script that orchestrates a local relay, app server, and Playwright browser to verify login, video publishing, and DM decryption flows. This satisfies the `smoke-agent` weekly task.
- Adds `scripts/agent/smoke-test.mjs`
- Verifies app functionality via `window.__bitvidTest__`
- Checks `decryptDM` integration from `js/dmDecryptor.js`
Co-authored-by: PR0M3TH3AN <[email protected]>