fix(aiops): correct host alert fallback and resolved stamp

apps/api/src/services/incident_service.py

@@ -1008,7 +1008,8 @@ class IncidentService:
             await repo.update_status(
                 incident_id=incident_id,
                 status="resolved",
-                updated_at=now_taipei(),
+                updated_at=incident.updated_at,
+                resolved_at=incident.resolved_at,
             )
             logger.info("resolve_db_updated", incident_id=incident_id)
         except Exception as e:

apps/api/src/services/telegram_gateway.py

@@ -90,6 +90,13 @@ def _smart_truncate(text: str, limit: int, suffix: str = "…[截斷]") -> str:
     return text[:limit] + suffix
 
 
+def _format_resolved_guard_stamp(resolved_at: datetime | None) -> str:
+    """格式化 ADR-071-D 已解決狀態守衛文案。"""
+    if resolved_at is None:
+        return "✅ 此事件已解決"
+    return f"✅ 此事件已於 {resolved_at.strftime('%Y-%m-%d %H:%M')} 解決"
+
+
 # =============================================================================
 # Long Polling 配置 (Phase 5 內網修復)
 # =============================================================================
@@ -3568,7 +3575,6 @@ class TelegramGateway:
                 return None
 
             if incident.status in (IncidentStatus.RESOLVED, IncidentStatus.CLOSED):
-                resolved_at = incident.resolved_at.strftime("%Y-%m-%d %H:%M") if incident.resolved_at else "未知時間"
                 await self._answer_callback(
                     callback_query_id,
                     "blocked",
@@ -3577,7 +3583,7 @@ class TelegramGateway:
                 try:
                     separator = "──────────────"
                     safe_original = html.escape(original_text) if original_text else ""
-                    stamp = f"✅ 此事件已於 {resolved_at} 解決"
+                    stamp = _format_resolved_guard_stamp(incident.resolved_at)
                     await self._send_request("editMessageText", {
                         "chat_id": self.chat_id,
                         "message_id": message_id,