Mutation responses now carry invalidation via two transports:
1. JSON body: {"result": ..., "invalidate": ["user"]}
2. HTTP header: X-Mizan-Invalidate: user, notifications
Both are set on every mutation response. The JSON body is consumed
by the client runtime (mizanCall). The header is consumed by Edge
for CDN cache purging and by XHR responses for htmx-style apps.
Header format: comma-separated contexts, semicolon-separated params.
X-Mizan-Invalidate: user;user_id=5, notifications
Also: _resolve_invalidation and _format_invalidate_header extracted
as reusable helpers for when return-type branching adds HttpResponse
support (view-path mutations will only use the header transport).
Updated ROADMAP.md with full v1 plan including both transports,
return-type branching, affects_params, and Edge manifest.
270 Django tests pass.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>