fix(drift_narrator): 補寫 narrative_text 到 DB + drift_repository.update_narrative

apps/api/src/repositories/drift_repository.py

@@ -154,6 +154,15 @@ class DriftReportRepository:
             )
 
 
+    async def update_narrative(self, report_id: str, narrative: str) -> None:
+        """更新 AI 人話摘要 (Phase 30 ADR-067)"""
+        async with get_db_context() as db:
+            await db.execute(
+                text("UPDATE drift_reports SET narrative_text = :narrative WHERE report_id = :report_id"),
+                {"report_id": report_id, "narrative": narrative},
+            )
+
+
 _drift_repo: DriftReportRepository | None = None