approval.respond rode the generic 30s RPC deadline while the backend
honors an answer for the whole approvals.timeout window (default 300s).
A WebSocket write stalled behind a long LLM stream killed the client's
respond long before the backend would, surfacing the red
"request timed out: approval.respond" toast and apparently freezing
the session.
The RPC now carries an explicit 330s deadline (300s window + drain
margin), ambientRequestFor forwards per-call deadlines it was silently
dropping, and a deadline failure retries once — resolve_gateway_approval
pops the queue entry before committing, so a duplicate resolve is a
harmless resolved: 0.
Fixes#55433
02b282a5d4