concurrency.sx: persist/append-expect refuses an append when the stream
advanced past the caller's expected seq, returning {:conflict :expected
:actual} instead of crashing or overwriting. persist/conflict? + accessors.
Phase 2 complete, 54/54.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
project.sx: projection state {:value :seq}; persist/project folds the whole
stream, persist/project-resume folds only the tail so read models update
incrementally. Pure step (value event)->value. 37/37.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>