fix: predictions row carries arm run_id under shared gate_log; drain evolve gather on failure (algo #6)

tests/unit/test_harness_inference.py

@@ -117,8 +117,9 @@ def harness_log(tmp_path: Any, request: Any) -> HarnessLog:
     """创建临时 HarnessLog 实例。
 
     使用 test 节点名称的 hash 作为 db 文件名，避免冲突。
-    run_id 固定为 "test-run"，实际 run_inference 中传入的 run_id
-    由 HarnessLog.insert 自动覆盖为 HarnessLog 构造时的值。
+    实例 run_id 固定为 "test-run"；predictions 行的 run_id 由 inference
+    record 显式携带（run_inference 传入值），不回落实例 run_id——
+    连续并发 gate 共享单一 HarnessLog 的契约。
     """
     db_name = f"harness_{id(request)}.db"
     db_path = str(tmp_path / db_name)
@@ -528,8 +529,9 @@ class TestPredictionAlwaysWritten:
         assert result.correct == 0
         assert result.stop_reason_counts.get("error") == 1
 
-        # 验证 DB 中的记录（HarnessLog.insert 使用构造时的 run_id）
-        rows = harness_log.query("SELECT * FROM predictions WHERE run_id = ?", ("test-run",))
+        # 验证 DB 中的记录（record 显式携带 run_inference 的 run_id，
+        # 不再回落 HarnessLog 实例 run_id——连续并发 gate 共享 log 的契约）
+        rows = harness_log.query("SELECT * FROM predictions WHERE run_id = ?", ("run-error",))
         assert len(rows) == 1
         assert rows[0]["stop_reason"] == "error"
         assert rows[0]["prediction"] is None
@@ -553,8 +555,8 @@ class TestPredictionAlwaysWritten:
         )
 
         assert result.total == 1
-        # HarnessLog.insert 使用构造时的 run_id
-        rows = harness_log.query("SELECT * FROM predictions WHERE run_id = ?", ("test-run",))
+        # record 显式携带 run_inference 的 run_id（共享 log 契约）
+        rows = harness_log.query("SELECT * FROM predictions WHERE run_id = ?", ("run-parse-err",))
         assert len(rows) == 1
         assert rows[0]["prediction"] is None
 
@@ -612,7 +614,7 @@ class TestNonScalarPrediction:
         )
 
         assert result.total == 1
-        rows = harness_log.query("SELECT * FROM predictions WHERE run_id = ?", ("test-run",))
+        rows = harness_log.query("SELECT * FROM predictions WHERE run_id = ?", ("run-nonscalar",))
         assert len(rows) == 1
         # prediction 被 JSON 序列化为字符串，不再是 Python list
         assert rows[0]["prediction"] == '["B"]'