[followup] exposeproxy TestUDPSessionIsPromotedOnlyByAGuestReply flakes under whole-suite load

open   by a73x

Labels: backlog

[claude 2026-08-14] Seen once in three full scripts/coverage.sh runs during unrelated per-vm-networks work: udp_test.go:194 (90s timing assertion) failed under load, preceded by a 'UDP session cap, dropping' warning; passed 20/20 in isolation. Timing-sensitive under parallel suite pressure — pin the nondeterminism (fake clock / cap headroom) or isolate the test.