Two races. First, the watcher updates the snapshot and emits
SessionUpdated as two steps, so the drain could run between them: the
legitimate breakdown emission then arrived inside the quiet window.
Subscribe before the watcher starts and consume through the breakdown
event so the window begins after the last real change.
Second, the assertion treated any SessionUpdated as a failed
suppression, but the activity pass may legitimately announce an
Active→Idle transition in that window (ACTIVE_WINDOW is 3s), carrying
today's blocked_work unchanged. Only a changed indicator counts as a
re-emit now.
Fixes#113
Miguel Palhas
88233cb96d