v0.42.0

One new author warning, no schema change, nothing blocks:
W-MANIFEST-DESCRIPTION-COPY names a set manifest that repeats the
description the root entry owns. 0 of the 56 set manifests in the eleven
content repositories carry one.

W-MANIFEST-DESCRIPTION-COPY: the description lives in the root entry (engine#268)

Since engine#246 each field of a set has one owner, and description
belongs to the root entry alone. Nothing checked it: validateManifestPair
reports E-MANIFEST-ENTRY-MISMATCH only for copies that differ, so an
identical copy in the set manifest passed and could drift later (it happened
in adaptive-learner-content-test#110). validateManifestPair now warns
W-MANIFEST-DESCRIPTION-COPY (params setId, path /sets/0/description)
whenever the set manifest carries a non-empty description: identical,
different (next to the mismatch error) or with the root silent. The other
root-owned fields may still be repeated identically.

A warning, so nothing blocks; measured over the eleven content repositories
on 2026-10-13, 0 of 56 set manifests carry one.