The decrypt-pass refactor hoisted partnerPub() above the loop and outside the
try, so a keyless partner (one who reset and hasn't re-set-up) or a fetch error
rejected the whole pass unhandled (setPlain never ran). Fetch the key lazily
inside the try and once, so an empty thread never fetches and a fetch failure
degrades to "can't decrypt" as before. Document the send-path staleness (a first
proactive send after a partner's key rotation uses the stale cached key) as a
known limitation alongside refreshPartnerPub.
peter
dce191f1c0