Passwords, channel secrets, pairing PINs, and private keys reached the DEBUG log and
the runs table in plain text: every chat run stored its channel secret inside the
Conversation repr, and --password, --secret, channel links, and config set device_pin
were stored as typed. meshterm.core.secrets now hides each one as <secret> by its
shape (a secret-named key, record, set operation, or dataclass field; bytes; a Secret;
a remote `password`/`set guest.password` command; name=value in text), and by value
for each secret MeshTerm has read or sent. Both log handlers and the runs table go
through it, always. The remote CLI history keeps `password ` without its value. Schema
v20 hides the secrets that older versions stored.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>