fix(gitea): expose bundle backup restore readback

ops/monitoring/alerts-unified.yml

@@ -1581,6 +1581,23 @@ groups:
           description: "Gitea private bundle manifest、bundle、checksum 或 freshness 有缺口；public repo search 不能代表完整備份。"
           runbook: "先讀 awoooi_gitea_bundle_* 指標找缺少的 repo，執行 scripts/backup/gitea-repo-bundle-backup.sh 產生 bundle 並同步到 188；不得刪 repo、不得 restore 到 production、不得讀 token。"
 
+      - alert: GiteaPrivateBundleRestoreDryRunMissing
+        expr: absent(awoooi_gitea_bundle_sample_restore_dry_run_ok{host="188"}) or awoooi_gitea_bundle_sample_restore_dry_run_ok{host="188"} == 0
+        for: 30m
+        labels:
+          severity: critical
+          layer: host-backup
+          component: gitea-private-bundle
+          host: "188"
+          team: ops
+          alert_category: infrastructure
+          notification_type: TYPE-3
+          auto_repair: "false"
+        annotations:
+          summary: "188 Gitea private repo bundle 還原 dry-run 未通過"
+          description: "Gitea bundle 備份需要 sample restore dry-run 證明可還原；bundle 存在不等於 restore confidence。"
+          runbook: "在 188 執行 scripts/backup/gitea-bundle-sample-restore-dry-run.sh --repo wooo/awoooi --write-textfile；只允許暫存目錄 dry-run，不得 restore 到 production，不得刪 repo，不得讀 token。"
+
       - alert: BackupCoverageDomainStale
         expr: awoooi_backup_coverage_domain_fresh == 0
         for: 15m