[bug] stale-cleanup retry mkdir failure path falls back to generic -32000

[kiki830621]

Problem

che-telegram-all-mcp-wrapper.sh:159 stale-cleanup retry path exits with stderr only — no JSON envelope to stdout. Race window:

rm -rf "$LOCK_DIR"
mkdir "$LOCK_DIR" 2>/dev/null || {
    echo "Failed to claim lock (stale-cleanup race)." >&2
    exit 1
}

If concurrent wrapper recreates lock dir between rm -rf and our mkdir → fall back to generic -32000. Race rare but reachable.

Surfaced by Codex (P3 #7).

Expected

Call emit_mcp_error_response before exit 1 in the retry-fail branch too, distinct message indicating race.

Priority

P3 — race rare in single-user; polish.

Source: surfaced during /idd-verify che-msg#31 (sister bug from verify ensemble — Codex + Devil's Advocate flagged convergently)

Verify report: #90 (comment)
Related issue: PsychQuant/che-msg#31
Related PR: psychquant-claude-plugins#90 (PR-1 ships v1.3.2)

🤖 Filed by /idd-verify Step 5b follow-up triage.