pub(crate) fn protect_answer(draft: &mut Draft)Expand description
Answering an encrypted message: the answer is encrypted when every key is
known. The copy kept with the draft stays as it came, encrypted: it opens
only at Send, in memory (sioul_sync::send::build_draft), never in clear
on a disk, nor in the sharing, which carries drafts to every device. Until
19 October 2026 its decrypted text was written there (seal_clear_drafts
seals those copies again).