feat: add shared Select facade

[Bindy-lbb]

Closes #31

Summary

• add the public Select facade over Ant Design with a stable ui-select hook
• preserve Ant Design's option/value API while exposing an invalid state for product forms
• cover the export, accessible name, invalid state and stable hook in the primitive contract tests

Validation

• npm run format:check
• npm run lint
• npm run typecheck
• npm run test (24 passing)
• npm run build
• npm run check:dist-tokens
• npm run test:pack
• npm run test:visual -- --grep 'aligns reading content' (1 passing)

npm run check reached the full screenshot suite and found a pre-existing 67,403-pixel drift in the showcase-light.png baseline. The showcase has no Select usage, so this change cannot affect that page; I left the unrelated baseline untouched.

[PeterGuy326]

Reviewed head 4a82fce. Clean facade: keeps Ant Design's SelectProps/option model intact, layers invalid -> status='error' + aria-invalid, and exposes the stable .ui-select hook so product code stops re-deriving it. The aria-invalid ?? invalid order respects an explicit aria-invalid. CSS adds the minimal width:100% baseline; tests cover the hook, invalid state and accessible name. No blockers. Approving — unblocks roleweave #522.