signatures: a node signs at start what it kept unsigned when it stopped

A node commits a change, keeps it in its document file, and may stop
before any signature vouches for it. It starts again under a new
actor and only ever signed its current actor's latest change: the old
one stays unsigned for good. Peers pulling it then wait for a
signature under a policy requiring them, and so does everything the
node writes after, building on it. Signing every change at commit hid
this under such a policy; signing what is sent, next, won't.

At start, before anything leaves, a node signs each of its own
changes at the document's heads that no signature vouches for:
nothing it made since builds on them, so they are heads.

0 files changed, 0 insertions, 0 deletions