feat: add MilestoneTracker component and wire into VaultDetail

[go165]

Summary

• add a reusable, token-driven MilestoneTracker component for VaultDetail milestone progression
• wire the tracker into VaultDetail and document the component in the design system
• add focused RTL coverage for MilestoneTracker and VaultDetail integration
• include a small Field accessibility/parser fix so repo-wide parsing and the existing Field test remain green

Verification

• npm test -- --run src/components/__tests__/MilestoneTracker.test.tsx src/pages/__tests__/VaultDetail.test.tsx src/components/__tests__/Field.test.tsx
• npx eslint src/components/MilestoneTracker.tsx src/components/__tests__/MilestoneTracker.test.tsx src/pages/__tests__/VaultDetail.test.tsx src/components/Field.tsx
• git diff --cached --check

Notes

• npx tsc --noEmit --pretty false still reports unrelated repository baseline issues outside this change, including existing App/Layout/VaultCard/test config errors and other pre-existing test type gaps.
• Payout wallet if reward-eligible: 0x1f0130669ca6fd02e025a984cc038f139df19a2f