fix(backup): correct receipt aggregate promql

docs/LOGBOOK.md

@@ -53859,7 +53859,7 @@ production browser smoke:
 - Gitea main `0acda9f72 fix(backup): add alert receipt contract` 已經由後續 main deploy 帶入 runtime；CD `#4527` 讀回 job succeeded、deploy marker `374d4e4 -> dc4f0ec`、production deploy readback matched、success notification。
 - 受控同步新版 `backup-health-textfile-exporter.py` 到 110 `/home/wooo/scripts/` 與 188 `/home/ollama/scripts/`，均先備份舊檔；立即刷新 `backup_health.prom`，110 讀回 `awoooi_backup_alert_receipt_stage_expected_info` 88 條、188 讀回 12 條。
 - `scripts/ops/deploy-alerts.sh` dry-run 後正式套用：遠端規則備份、hash 驗證、Prometheus reload 與 key-rule verifier 成功；Prometheus 已載入 165 條規則。
-- runtime readback 確認 `BackupAlertReceiptMetricMissing` / `BackupAlertReceiptMetricMissing188` inactive，`BackupAlertReceiptStageMissing` rule health ok。初版逐 stage alert 會產生 100 條 pending，已立刻改成每 `host / receipt_channel` 一條聚合 alert，明細保留在 `awoooi_backup_alert_receipt_stage_fresh == 0`。
+- runtime readback 確認 `BackupAlertReceiptMetricMissing` / `BackupAlertReceiptMetricMissing188` inactive，`BackupAlertReceiptStageMissing` rule health ok。初版逐 stage alert 會產生 100 條 pending，已立刻改成每 `host / receipt_channel` 一條聚合 alert，明細保留在 `awoooi_backup_alert_receipt_stage_fresh == 0`；聚合 alert expression 必須使用 `== bool 0`，否則 PromQL 會把每個缺口 series 的值保留為 `0`，`sum(...)` 後仍為 `0`。
 
 **驗證結果**：
 - `python3.11 -m pytest scripts/ops/tests/test_backup_health_textfile_exporter.py scripts/reboot-recovery/tests/test_reboot_p0_operational_contract.py ops/runner/test_cd_controlled_runtime_profile.py -q -p no:cacheprovider`：`65 passed`。

ops/monitoring/alerts-unified.yml

@@ -1649,7 +1649,7 @@ groups:
           runbook: "部署新版 scripts/ops/backup-health-textfile-exporter.py 到 188，刷新 /home/ollama/node_exporter_textfiles/backup_health.prom；不得送測試 Telegram、不得讀 token、不得 restore 到 production。"
 
       - alert: BackupAlertReceiptStageMissing
-        expr: sum by (host, receipt_channel) (awoooi_backup_alert_receipt_stage_fresh == 0) > 0
+        expr: sum by (host, receipt_channel) (awoooi_backup_alert_receipt_stage_fresh == bool 0) > 0
         for: 30m
         labels:
           severity: warning

scripts/ops/backup-alert-label-contract-check.py

@@ -144,7 +144,7 @@ def static_check(path: Path, baseline_path: Path) -> list[str]:
     rule = _require_alert(alerts, "BackupAlertReceiptStageMissing")
     _require_contains(
         str(rule.get("expr", "")),
-        "sum by (host, receipt_channel) (awoooi_backup_alert_receipt_stage_fresh == 0) > 0",
+        "sum by (host, receipt_channel) (awoooi_backup_alert_receipt_stage_fresh == bool 0) > 0",
         "BackupAlertReceiptStageMissing expr",
     )
     text = _annotation_text(rule)

scripts/ops/backup-alert-live-visibility-check.py

@@ -190,7 +190,7 @@ def _escrow_required_alerts(prometheus_url: str, host: str, timeout: int) -> lis
 def _receipt_stage_required_alerts(prometheus_url: str, host: str, timeout: int) -> list[RequiredAlert]:
     expr = (
         "sum by (host, receipt_channel) "
-        f'(awoooi_backup_alert_receipt_stage_fresh{{host="{host}"}} == 0) > 0'
+        f'(awoooi_backup_alert_receipt_stage_fresh{{host="{host}"}} == bool 0) > 0'
     )
     rows = _prom_query(prometheus_url, expr, timeout)
     required: list[RequiredAlert] = []

scripts/reboot-recovery/tests/test_reboot_p0_operational_contract.py

@@ -363,7 +363,7 @@ def test_backup_alerts_cover_188_gitea_mirror_subtree() -> None:
     assert "BackupAlertReceiptMetricMissing" in alerts
     assert "BackupAlertReceiptStageMissing" in alerts
     assert "awoooi_backup_alert_receipt_expected_info" in alerts
-    assert "sum by (host, receipt_channel) (awoooi_backup_alert_receipt_stage_fresh == 0) > 0" in alerts
+    assert "sum by (host, receipt_channel) (awoooi_backup_alert_receipt_stage_fresh == bool 0) > 0" in alerts
     assert "$labels.receipt_channel" in alerts
     assert "$value" in alerts
     assert "required_alert/scope/stage/required_notification_type" in alerts