Only a tracked clan's roster gates a player's polls

The first day of the roster gate was measured against the review that proposed it. Battle-log fetches halved as promised and the web door's cost fell 97%, but capture gaps rose from 0.1% to 1.5%: a roster read every 4 to 24 hours (an incidental clan, polled only because a recorded player sits in it) was holding back the battle-log polls of players who then played a full 25-battle session before it noticed. Now only a tracked clan's roster, read every 15 to 60 minutes while members play, can gate. Also today: a player's last-seen stamp moves at most daily instead of hourly (it was the busiest write left), the per-battle observer table is no longer written, and collectors below 2.0.30 are refused work with a clear message instead of served through the old long-poll path.