HA stage 0: health reads workers registry, daily pg_dump timer, backup freshness in monitor (#48)

Co-authored-by: host <host@test.local>

deploy/monitor.sh

@@ -18,6 +18,9 @@
 #   docker_postgres：docker ps 里 codex-postgres 在运行
 #   disk：磁盘使用率 < 90%（默认看 /var/lib/codex-app-server，不存在则看 /）
 #   app_dir：/opt/codex-app-server 目录存在
+#   backup：最近的 cloud-backup-*.sql 在 36 小时内（每天一次定时备份，
+#           HA 阶段 0；目录默认 /var/lib/codex-app-server/backups，可用
+#           MONITOR_BACKUP_DIR 覆盖）
 #
 # 输出示例（单行 JSON，值只会是 pass/fail，不含任何密钥）：
 #   {"overall": "pass", "checks": {"server": "pass", ...}}
@@ -105,16 +108,32 @@ check_app_dir() {
   if [ -d "$APP_DIR" ]; then echo pass; else echo fail; fi
 }
 
+check_backup() {
+  # 备份新鲜度：BACKUP_DIR 里最近的 cloud-backup-*.sql 在 36 小时内
+  # （每天一次，36 小时容忍一次失败 + 时区/夏令时抖动）。目录或文件
+  # 缺失一律 fail——备份制度断了必须在 monitor 里可见，不能静默。
+  BACKUP_DIR=${MONITOR_BACKUP_DIR:-/var/lib/codex-app-server/backups}
+  NEWEST=$(ls -t "$BACKUP_DIR"/cloud-backup-*.sql 2>/dev/null | head -1 || true)
+  if [ -z "$NEWEST" ]; then echo fail; return; fi
+  MTIME=$(stat -c %Y "$NEWEST" 2>/dev/null || true)
+  case "$MTIME" in
+    ''|*[!0-9]*) echo fail; return ;;
+  esac
+  NOW=$(date +%s)
+  AGE=$((NOW - MTIME))
+  if [ "$AGE" -lt 129600 ]; then echo pass; else echo fail; fi
+}
+
 run_checks() {
   S=$(check_server); W=$(check_worker); H=$(check_health)
   P=$(check_postgres); D=$(check_docker_postgres)
-  K=$(check_disk); A=$(check_app_dir)
+  K=$(check_disk); A=$(check_app_dir); B=$(check_backup)
   OVERALL=pass
-  for v in "$S" "$W" "$H" "$P" "$D" "$K" "$A"; do
+  for v in "$S" "$W" "$H" "$P" "$D" "$K" "$A" "$B"; do
     if [ "$v" != "pass" ]; then OVERALL=fail; break; fi
   done
-  printf '{"overall": "%s", "checks": {"server": "%s", "worker": "%s", "health": "%s", "postgres": "%s", "docker_postgres": "%s", "disk": "%s", "app_dir": "%s"}}\n' \
-    "$OVERALL" "$S" "$W" "$H" "$P" "$D" "$K" "$A"
+  printf '{"overall": "%s", "checks": {"server": "%s", "worker": "%s", "health": "%s", "postgres": "%s", "docker_postgres": "%s", "disk": "%s", "app_dir": "%s", "backup": "%s"}}\n' \
+    "$OVERALL" "$S" "$W" "$H" "$P" "$D" "$K" "$A" "$B"
   if [ "$OVERALL" = "pass" ]; then return 0; else return 1; fi
 }