One newest-first feed merging the coordination journal (overlay/alias/fork/merge/
binding decisions, with actor + payload) and shard change signals (page
source_rev / mtime). Each entry carries provenance: the originating shard for an
edit, or 'coordination' (and the actor) for a decision. Non-temporal revision
tokens are skipped gracefully. Derived/recomputable; notify-streaming later.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
