Codex/mac mps runner - Support Mac MPS local startup

[lnn2hc2112]

Summary

• Make the Mac launcher scripts executable and more robust for local startup.
• Prefer the repo-local Python venv and bundled local Node/npm when available.
• Fix Next/Turbopack project root config so the web UI can run reliably from the launcher.
• Add missing frontend helper modules used by the existing UI components.

Tested

• Installed Python and frontend dependencies locally.
• Loaded Kronos model on Apple Silicon MPS.
• Ran prediction successfully through the API and UI.
• Verified npm run build passes for webui-next.

Notes

• Local runtime folders such as .venv, .tools, node_modules, logs, PID files, and prediction results are ignored and not included in this PR.
• This PR is only for Mac/MPS startup support; prediction pipeline/backtest changes are being kept separate.

[lnn2hc2112]

All checks passed. This PR is ready for review.