Block render cache (per-block, version-keyed)

[tayebmokni]

Summary

Per-block server-render cache per doc 07 §15.5 keyed by block:{block_type}:{attrs_hash}:{content_version}. Bumping content_version is the invalidation mechanism (one Redis INCR per relevant content change). Opt-in per block type via the server-render contract (cacheable: true | false | { ttl, version_tags: [...] }). Static blocks (paragraph, heading) cache effectively forever.

Design reference

• docs/07-media-performance.md §15.5

Acceptance criteria

• BlockRenderCache interface; Redis-backed implementation
• Key format: block:{block_type}:{attrs_hash}:{content_version}
• content_version bumped via INCR on relevant content changes (e.g., post writes bump the global post version)
• Static blocks (paragraph, heading) cache without content_version (attribute-only)
• cacheable opt-in declared in server-render contract per block type
• Cache used by core blocks: core/latest-posts, core/post-list, core/comments
• Tests verify miss → render → hit → invalidate flow

Dependencies

#fragment-cache

Complexity

M

[tayebmokni]

Closing — shipped in the final-wave PR (#487-#492). Auto-close only fires for first ref.