Prev/next browsing with position feedback. Purely props-driven — no fetching, no app state. ## Tasks - [ ] `src/components/NavigationControls.tsx`: props `{ currentIndex, totalCount, onPrevious, onNext }` - [ ] Buttons disabled at the ends; visible progress text like `3 / 10` - [ ] `aria-label`s on both buttons (`aria-disabled` or `disabled` semantics), focusable via keyboard - [ ] `src/components/NavigationControls.css` imported by the component - [ ] Tests: snapshot; clicking Previous/Next calls the right handler; disabled at boundaries (no call) ## Acceptance criteria - [ ] `npm run lint` / `npm test` / `npm run build` pass, jsx-a11y clean - [ ] Semantic HTML, explicit prop types, named export Part of M2 — Core app (due Tue 8/9). Branch `feat/<n>-navigation` from main after PR #3 merges. Inline fixture props — never the network.