Add audit Select and polish shell controls

[MaggieAppleton]

Summary

• add a shared Base UI-backed Select composition to @chopin/visuals
• adopt it only in the design audit field specimen
• refine button, field, radio, link-focus, busy, and reduced-motion presentation

This intentionally does not migrate product pickers or change application behavior. Stacked on #178.

Verification

• 59 focused tests pass
• 1,519 repository tests pass; 2 PostgreSQL-environment skips
• bun run types
• bun run ci
• bun run build
• git diff --check

Component preview