Three fixes on top of the pane-id PR, from my own read and the reviewer's:
- stop() removed the spawnedBy record BEFORE the delegate accepted the stop. A
delegate that threw left the pane alive with its owner forgotten, so the retry
fell into the ambiguous branch and refused the id for good. Remove after.
- list() deduplicated on the raw pane id. Pane ids are per-daemon counters, so
two daemons can each hold w1:p1 on different panes, and one of the two real
agents was silently dropped from fleet_list and every view built on it. The
key is now (owning daemon, pane id). Delegates sharing one daemon still
collapse, which is what the dedupe was for.
- The class javadoc still stated the single-herdr-connection premise as fact,
next to the bullet this PR had just corrected for stop(). Fixed there too.
Also drops a redundantly qualified java.util.Collections.
Tests: 993 run, 0 failures, BUILD SUCCESS.