A record's HoldsIds was decided by its admission and trusted afterwards, so a
document changed after it was committed, or loaded and changed in place,
flushed under the header its admission-time content needed (Soul P7, P10).
HoldsIds now has one owner, the record's stored form, read when asked:
- a plain record: CultElementIds.Holds over its document, a scan that reads
and refuses nothing;
- a variant: the same scan over each override value, decoded with the codec
the record was built with (the cache's, or the attached cache's at load);
- a variant built with no codec (a store that loaded it with no cache) cannot
see its values and counts as holding an id, so a store never writes an
unmarked header over ids it could not see.
Cut: the admission path that set HoldsIds on plain records, on variants from
their resolved copies, and on flattened records; the internal setter and its
backing flag; IdPlan.HeldIds and IdPlan.HoldsIds. The Mesh typed write reads
Holds off the document it writes. Admission keeps its own id counting
(IdPlan.Count) for IdsInMemoryOnly.
Tests: an id added to a committed or loaded deck after admission marks a
PushAll v3, and taking it away unmarks it; a variant read without a codec
counts as holding ids while the same record read with one does not.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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