Desktop archives sessions via PATCH /api/sessions/{id} -> set_session_archived,
but the TUI gateway had no equivalent JSON-RPC method, so TUI clients had to
keep every session visible or delete it permanently. Open PR #47184 added this
against the pre-split server.py layout and resolves only live runtime sessions;
this lands the method on current main next to session.set_hidden with the same
two-tier resolution: live runtime id first (unpersisted drafts defer via
pending_archived, applied by _ensure_session_db_row like pending_hidden), then
a stored id/key resolved through the profile db, covering the historical rows
the session.list picker shows. Contract declared in tui_gateway/contracts and
rendered into the generated TS/OpenRPC catalog.
Fixes https://github.com/NousResearch/hermes-agent/issues/47168
d3f9ba3cd5