feat(governance): attach km archive history to dedupe groups

apps/api/tests/test_ai_governance_endpoints.py

@@ -471,6 +471,20 @@ class TestKmReviewDraftDedupe:
                     owner_action="review_canonical_and_archive_duplicate_drafts",
                     writes_on_read=False,
                     can_archive_without_owner_approval=False,
+                    archive_history=[
+                        DispatchItem(
+                            id="dispatch-archive-001",
+                            governance_event_id="event-001",
+                            event_type="knowledge_degradation",
+                            dispatch_status="succeeded",
+                            executor_type="hermes_km_review_dedupe_owner_archive",
+                            proposed_action="Owner archived duplicate KM drafts",
+                            created_at=NOW,
+                            workflow_stage="km_duplicate_archive_after_owner_approval",
+                            dry_run_plan_fingerprint="sha256:" + "a" * 64,
+                            archived_count=2,
+                        )
+                    ],
                 )
             ],
         )
@@ -490,6 +504,10 @@ class TestKmReviewDraftDedupe:
         assert data["groups"][0]["canonical_entry_id"] == "km-canonical"
         assert data["groups"][0]["writes_on_read"] is False
         assert data["groups"][0]["can_archive_without_owner_approval"] is False
+        assert data["groups"][0]["archive_history"][0]["executor_type"] == (
+            "hermes_km_review_dedupe_owner_archive"
+        )
+        assert data["groups"][0]["archive_history"][0]["archived_count"] == 2
 
     def test_governance_event_tag_extraction(self):
         assert _extract_governance_event_id_from_tags([
@@ -524,6 +542,27 @@ class TestKmReviewDraftDedupe:
         groups = _build_km_review_draft_dedupe_groups(
             rows,
             {"event-001": "km-canonical"},
+            {
+                "event-001": [
+                    DispatchItem(
+                        id="dispatch-recheck-001",
+                        governance_event_id="event-001",
+                        event_type="knowledge_degradation",
+                        dispatch_status="succeeded",
+                        executor_type="hermes_km_stale_ratio_recheck",
+                        proposed_action="Rechecked stale ratio",
+                        created_at=NOW,
+                        workflow_stage="stale_ratio_recheck",
+                        stale_ratio_snapshot={
+                            "stale_count": 10,
+                            "total_count": 100,
+                            "stale_ratio": 0.1,
+                            "threshold": 0.2,
+                            "stale_days": 7,
+                        },
+                    )
+                ]
+            },
         )
 
         first = groups[0]
@@ -532,6 +571,8 @@ class TestKmReviewDraftDedupe:
         assert first.preferred_source == "dispatch_context"
         assert first.duplicate_entry_ids == ["km-latest"]
         assert first.writes_on_read is False
+        assert first.archive_history[0].executor_type == "hermes_km_stale_ratio_recheck"
+        assert first.archive_history[0].stale_ratio_snapshot["stale_ratio"] == pytest.approx(0.1)
 
     def test_archive_endpoint_requires_owner_shape_and_returns_audit_result(self, client):
         """Owner 批准後的 archive endpoint 應回傳 KM write 與 audit write 結果。"""