ObserveAsync, ReactiveAsync and RefreshAsync read a snapshot without a
Sequence, so an older change admitted before the read but delivered after it
overwrote the newer value.
CultCache.GetWithSequence(key) returns the document and the cache's Sequence,
read together under the gate. A cache-backed CultMesh handle passes it to its
mirrors; each mirror subscribes first, then adopts the sequenced read under its
own gate and takes that Sequence as applied, so a straggler at or below it
drops. RefreshAsync on both mirrors uses the same adoption path. Public Mesh
surface unchanged. The read is non-generic because the Mesh route needs the
untyped document for same-schema conversion.
Contract: only Watch/WatchRecord changes carry Sequence; OnUpdate-derived
CultNet streams have no ordering or stale protection; schema-alias handles and
removals are not stale-protected; the sequence constructor argument changed
CultCacheDocumentChange<T>'s binary signature.
Tests: ObserveAfterNewerSnapshotIgnoresStraggler and
RefreshIgnoresStragglerOlderThanSnapshot (observed and reactive cases) fail on
4562340; SequencedReadReflectsEveryChangeAtOrBelowItsSequence.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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