A soft nudge advisory belongs to one continuous on-task stretch in an allowed
app. Guard it with an on-task-stretch epoch (advanced on session reset and on
any non-on-task-match observation) instead of a session-only counter, and clear
the advisory on leaving the allowed app, so a stale 'Heads up' never resurfaces
after a drift episode.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>