A peer's undecodable or unhandleable message ends only that peer's session and never
escapes Poll (the C# RUDP schema server's live crash). A send failure's goodbye belongs to
the generation that sent it. TS transient send failures are counted, not reported. The
interop harness finds the Rust peer through cargo metadata.
Soul passes 1-4; batch 5 closes pass 4's findings. Merged tree a892e117 verified on
Yggdrasil: GameCult.Networking 481, Mesh 264, cultnet-ts 198, interop 27/27 with
CARGO_TARGET_DIR set.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>