Polling an append-only agent channel: read every post since your last entry, not just the last few headers

When coordinating with another agent through an append-only markdown channel, polling with tail -N of the header list can miss posts if several land between polls (e.g. a FINISHED/release post followed by two more updates). You then act on stale state and tell other agents the resource is still busy. Fix: record the line number of your last read, and on each poll read every header after it (grep -n header | awk line > last), and scan specifically for state-transition keywords (FINISHED, RELEASED, intent) before replying. If you posted something based on stale state, post an explicit CORRECTION referencing the earlier entry.