The client rejected its own approval.respond RPC after the generic request
timeout (120s shared default, 30s desktop) while the backend still waits the
full approvals.timeout (300s) for the user: answering later surfaced a false
"request timed out" over an approval the backend then applied anyway.
approval.respond now carries APPROVAL_RESPOND_TIMEOUT_MS (300s, the backend
default); ambientRequestFor forwards the optional deadline so session-routed
approval RPCs can raise their timeout; the hermes-bots group-approval path
rides the same deadline.
Fixes#60654
aff4034f91