PERMANENTLY delete a saved session from the caller's PRIVATE library. Fast — no log rewrite in the request: the entry is hidden at once (stops listing; fetch/resume answer 404) and one erasure-ledger line (ids and dates only) per item — the private collection and its session member — is appended. That line is the durable commitment: the batched erase worker (collector/erasure.deferred_erase_loop) erases every stored version through the GDPR hard-erase path within LIBRARY_ERASE_WINDOW_HOURS, many deletes in one log rewrite, and replay_ledger re-applies it after any restore. No grace period, no undo. Answers 202 erasure_scheduled.

Account-scoped — a signed-in human can only delete their OWN entries (anything else is 404 and nothing is scheduled). Accepts a collection id, a session id, or a name/label (?name=). Kept, and listed in retained: published copies in a workspace, buyers' copies and escrow, billing/entitlement records, forks of this entry, backups until they expire. Idempotent: a repeat answers 202 erasure_scheduled until the worker is done, then 200 already_erased; an unknown id is 404 as before.