feat: suppress sac-fail.count on shutdown (2.3.2-SAC)

Phase 4.2: SAC_SUPPRESS_FAIL_COUNT during lifecycle shutdown so restart during SAC deploy does not trip Telegram fallback. Add docs/sac-ingest.ru.md for SAC_TIMEOUT_SEC guidance, smoke test, and release manifest.

sac-client.sh

@@ -119,8 +119,20 @@ sac_reset_fail_count() {
  sac_write_fail_count 0
 }
 
+# Внутренний флаг: при shutdown/SIGTERM не крутить счётчик (restart во время SAC-deploy).
+sac_fail_count_increment_suppressed() {
+ case "${SAC_SUPPRESS_FAIL_COUNT:-0}" in
+ 1 | yes | true | on) return 0 ;;
+ esac
+ return 1
+}
+
 sac_increment_fail_count() {
  local n max
+ if sac_fail_count_increment_suppressed; then
+  write_log "SAC: пропуск sac-fail.count (shutdown/maintenance)"
+  return 1
+ fi
  max="${SAC_FALLBACK_FAILURES:-5}"
  n="$(sac_read_fail_count)"
  n=$((n + 1))