docs: design for diagnosis tree_data broken-link fix (TRM4 regression)

research-wiki/graph/edges.json

@@ -230,6 +230,11 @@
       "id": "metric:split-floor-and-representativeness",
       "label": "指标: floor 达标率 + test 代表性偏差",
       "type": "metric"
+    },
+    {
+      "id": "design:fix-diagnosis-tree-data-link",
+      "label": "修复诊断 tree_data 断链 bug（TRM4→TRM5 迁移 regression）",
+      "type": "design"
     }
   ],
   "links": [
@@ -456,6 +461,20 @@
       "relation": "measures",
       "evidence": "floor+代表性",
       "added": "2026-07-15T15:42:38.269455+00:00"
+    },
+    {
+      "source": "design:fix-diagnosis-tree-data-link",
+      "target": "design:results-driven-video-split",
+      "relation": "informs",
+      "evidence": "修复诊断 error_type 污染，恢复 video-split 多样性维真实信号",
+      "added": "2026-07-16T01:31:36.665025+00:00"
+    },
+    {
+      "source": "design:fix-diagnosis-tree-data-link",
+      "target": "schema:baseline-diagnosis",
+      "relation": "refines",
+      "evidence": "修正 error_type/evolution_target 列取值不再坍缩",
+      "added": "2026-07-16T01:31:37.792648+00:00"
     }
   ]
 }