Add CDN-ready headers, ROADMAP, fold runtime into mizan-react
CDN headers on context GETs (Edge-ready):
- Cache-Control: public, max-age=0, stale-while-revalidate=300
- Vary: Authorization, Cookie
- Deterministic JSON (sorted keys) for consistent cache keys
- Error responses: Cache-Control: no-store
- Mutation POSTs: Cache-Control: no-store
ROADMAP.md documents v1 deliverables and Mizan Cloud (Edge, Render,
Deploy) as closed-source products built on the open-source protocol.
mizan-runtime folded into mizan-react/src/runtime/ — framework-agnostic
split deferred until a second frontend adapter exists.
268 Django + 33 React tests pass.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>