Reorganize repository role layout

[plutoless]

Summary

• Move first-party clients into clients/: React/Vite web app under clients/web and Cardputer firmware under clients/cardputer.
• Move platform/prototype surfaces out of the Python runtime package: macOS executor supervisor to executor-apps/macos and design prototype to prototypes/design.
• Update operational references, ignore files, Docker/Vercel/release/install paths, stable docs, and stale eval imports for the role-based layout.

Test Plan

• .venv/bin/python -m pytest -> 661 passed, 1 warning
• cd clients/web && bun run test -> 213 passed
• cd clients/web && bun run build -> passed, with existing Agora bundle warnings
• swift test --package-path executor-apps/macos -> 117 passed
• pio test -d clients/cardputer -> 65 passed
• git status --short -> clean
• active stale-path grep for src/newbro/ui, exmaple-ui, example-ui, and retired frontend paths -> clean

Notes

• Docker build was not verified locally because Docker/OrbStack daemon was unreachable: Cannot connect to the Docker daemon.

[github-actions]

Vercel preview is ready.

https://newbro-puod81633-agora-devx.vercel.app