Initial commit: FA 2.0 Design System foundation

Token pipeline (Style Dictionary v4, DTCG format):
- Primitive tokens: colour palettes (brand, sage, neutral, feedback),
  typography (3 font families, 21-variant type scale), spacing (4px grid),
  border radius, shadows, opacity
- Semantic tokens: text, surface, border, interactive, feedback colours;
  typography roles; layout spacing
- Component tokens: Button (4 sizes), Input (2 sizes)
- Generated outputs: CSS custom properties, JS ES6 module, flat JSON

Atoms (3 components):
- Button: contained/soft/outlined/text × primary/secondary, 4 sizes,
  loading state, underline for text variant
- Typography: 21 variants across display/heading/body/label/caption/overline,
  maxLines truncation
- Input: external label, helper text, error/success validation,
  start/end icons, required indicator, 2 sizes, multiline support

Infrastructure:
- MUI v5 theme with full token mapping
- Storybook 8 with autodocs
- Claude Code agents and skills for token/component workflows
- Design system documentation and cross-session memory

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.claude/skills/review-component/SKILL.md

@@ -0,0 +1,49 @@
+---
+name: review-component
+description: Review a component against design system conventions
+argument-hint: "[ComponentName]"
+---
+
+Review a component against FA Design System conventions and report pass/fail for each check.
+
+**Component to review:** $ARGUMENTS
+
+**Instructions:**
+1. Read `docs/conventions/component-conventions.md` for the rules
+2. Read `docs/conventions/token-conventions.md` for token usage rules
+3. Read the component source file in `src/components/`
+4. Read the component's Storybook stories
+
+**Check each of these and report pass/fail:**
+
+### Code quality
+- [ ] Component uses TypeScript with proper types
+- [ ] Props interface exported with JSDoc on every prop
+- [ ] Uses `React.forwardRef` for interactive elements
+- [ ] Accepts and forwards `sx` prop
+- [ ] Uses `shouldForwardProp` for custom props on styled components
+
+### Theme compliance
+- [ ] NO hardcoded colours — all from `theme.palette.*`
+- [ ] NO hardcoded spacing — all from `theme.spacing()`
+- [ ] NO hardcoded typography — all from `theme.typography.*`
+- [ ] NO hardcoded shadows — all from `theme.shadows`
+- [ ] NO hardcoded border radius — all from `theme.shape.*`
+
+### Accessibility
+- [ ] Minimum 44px touch target on mobile
+- [ ] Visible focus indicator (focus-visible)
+- [ ] Appropriate ARIA attributes
+- [ ] Disabled state uses `aria-disabled`
+- [ ] Colour contrast meets WCAG 2.1 AA
+
+### Storybook coverage
+- [ ] Default story
+- [ ] All variants story
+- [ ] All sizes story (if applicable)
+- [ ] Disabled state
+- [ ] Loading state (if applicable)
+- [ ] Long content / overflow
+- [ ] autodocs tag present
+
+**Report format:** List each check with pass/fail and specific issues found. End with a summary and recommended fixes.