The WebUI clarify bridge resolved the prompt timeout from a local, divergent
copy (legacy clarify.timeout, 120s fallback) and treated 0 as invalid, so
agent.clarify_timeout: 0 (unlimited) could not be honored and there was no
way to make a clarification card wait for the user.
Resolve the timeout with the agent core's canonical resolve_clarify_timeout()
(clarify.timeout -> agent.clarify_timeout -> 3600, <= 0 = unlimited) against
the session's own profile config (the streaming worker thread does not inherit
the request's per-profile context), wait with a null deadline when unlimited,
and stop the frontend rendering an expired countdown for non-positive timeouts.
- api/streaming.py: per-session profile config resolution, canonical resolver
with a compatibility fallback, and an extracted _await_clarify_response()
helper that polls in 1s slices and honours cancellation.
- api/clarify.py: preserve timeout_seconds <= 0 and emit no expires_at.
- static/messages.js: _clarifyExpiryMs() returns 0 for non-positive timeouts
so the card stays up without a countdown.
- tests/test_sprint42.py: resolution matrix, per-session profile divergence,
unlimited resolve-later / cancel-exit, and no-expiry payload.
Closes#7159
Co-authored-by: nesquena-hermes <nesquena+hermes@gmail.com>
