Downloads whose effective classification is vs_nfd carry the documented
VS-NfD_ filename prefix (single source classificationFilenamePrefix() in
shared; ADR 0022 records the short form for file names). Effective
classification: the linked page's level; an attachment with unset pageId
(paste-then-insert, pond-level) FAILS CLOSED to the highest level of any
live page in its pond. The pond export ZIP adds a sibling
<file>.classification.txt companion with the full marking for classified
media, next to the manifest entry (#210). Documented in operations.md,
incl. the deliberate residual risk: the file's own content carries no
marking (recorded on #231, not hidden). Tests: prefixed classified
download, unchanged open download, fail-closed orphan both ways, ZIP
companion + manifest level.
Co-Authored-By: Claude Fable 5 (1M context) <noreply@anthropic.com>
