feat(hooks): add git hooks management (Husky + Vite+)

chore: formatting fix in RfcListItem component

fix: replace advisory ideate constraints with structural message format enforcement

feat: rules as card grid with RFC 2119 keyword badges

chore: biome lint auto-formatting

fix: enforce TDD hard gates and require user confirmation before plans

feat: add install tabs, missing sections, and disciplines tab to site

feat: add gaps mode to /arc:flow for missing journey detection

fix: harden brand skill against common AI pitfalls

refactor: extract brand knowledge into dedicated reference

refactor: separate UI fonts from brand fonts in typography reference

refactor: taste engine references typography and color docs

feat: add /arc:brand skill for visual identity systems

feat: add /arc:help command for context-aware skill discovery

feat: add UX laws, interaction physics, and typography references