Builds on the adapter list_channels() hook (cherry-picked from #43545 by
@Guoen0):
- plugins/platforms/simplex: implement list_channels() — enumerates
contacts (/contacts) and groups (/groups) over the live daemon
WebSocket into the channel directory. Returns None when the WS is
down so the directory falls back to session discovery instead of
wiping known targets.
- hermes send --list: merge configured-but-undiscovered platforms into
the listing. Previously a platform configured only via env (e.g. a
fresh SimpleX setup used for outbound sends) was silently omitted,
leaving users guessing at platform names.
- format_directory_for_display(): accept an explicit platforms view and
render empty platforms with a targeting hint instead of hiding them.
- docs: simplex hermes-send section.
Reported by Fedpostoffice on Discord (simplex missing from
hermes send --list; guessed platform names simplex-chat/simplex-relay).
7483745da7