The attachments panel of a classified page shows a persistent notice
naming the consequence (de+en): the file inherits the page's
classification but its content carries no marking (#212). The new
instance setting classification.uploadPolicy (default warn, documented;
the VS-NfD reference configuration blocks, #227) hardens the warning
into a server-side rejection (403 classified_upload_blocked) — enforced
in the upload service, not only in the UI. Tests: warning visible in the
local attachments pack; block enforced server-side with warn/block both
ways and open pages unaffected.
Co-Authored-By: Claude Fable 5 (1M context) <noreply@anthropic.com>
