fix(webhook): alertmanager 路徑 suggested_action 改用 kubectl_command

- 1399 行: suggested_action.value (RESTART_DEPLOYMENT) → kubectl_command
- 與 /alerts 路徑 887 行保持一致
- 修正 Telegram 顯示「kubectl rollout restart deployment/」後面空白的問題
- 2026-04-09 ogt: bug fix

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/api/src/api/v1/webhooks.py

@@ -1396,7 +1396,7 @@ async def alertmanager_webhook(
                 risk_level=risk_level.value,
                 resource_name=target_resource,
                 root_cause=root_cause,
-                suggested_action=analysis_result.suggested_action.value,
+                suggested_action=analysis_result.kubectl_command or analysis_result.suggested_action.value,
                 estimated_downtime=estimated_downtime,
                 hit_count=1,
                 primary_responsibility=primary_responsibility,