Run YAML cases through Rstest

[quanru]

Summary

• Add a Rstest-backed framework runner for Midscene YAML cases.
• Route the existing midscene <path> YAML CLI flow through generated Rstest test files.
• Isolate real YAML execution in a child process so Rstest workers orchestrate pass/fail behavior without owning browser/runtime teardown.
• Preserve Midscene report and output summary generation, with focused framework unit coverage.

Why

The UI testing framework needs YAML cases to participate in Rstest's runner model without replacing the repo's Vitest-based unit tests. Running Midscene/Puppeteer logic directly inside Rstest workers caused worker lifecycle issues, so the generated tests delegate the actual YAML run to a child process.

Validation

• pnpm run lint
• npx nx test @midscene/cli
• npx nx build @midscene/cli

[cloudflare-workers-and-pages]

Deploying midscene with    Cloudflare Pages

Latest commit:	35900a2
Status:	✅  Deploy successful!
Preview URL:	https://ece3dfdb.midscene.pages.dev
Branch Preview URL:	https://codex-rstest-yaml-runner.midscene.pages.dev

View logs

[fi3ework]

i'lll start a new branch in Rstest to joint development with this branch in Midscene.