refactor: share INFRA stop-reason set from core.evolution

app/harness/validate.py

@@ -27,6 +27,7 @@ from loguru import logger
 from app.harness.gate_ladder import BaselineCache, skill_hash
 from app.harness.question_units import build_units, flatten_units, unit_correctness_view
 from core.evolution import (
+    INFRA_STOP_REASONS,
     GateParams,
     GateVerdict,
     RejectedEdit,
@@ -35,6 +36,10 @@ from core.evolution import (
     pair_block,
 )
 
+# INFRA_STOP_REASONS 复用 core.evolution.diagnose 的单一定义（M-2）：INFRA 故障
+# stop_reason（推理侧基础设施错误，非模型答错）在诊断与 gate 两处必须同口径，
+# 避免各自维护副本致未来漂移。
+
 if TYPE_CHECKING:
     from app.harness.inference import InferenceResult
     from app.harness.log import HarnessLog
@@ -231,11 +236,6 @@ def _load_run_rows(
     return normalized
 
 
-# INFRA 故障 stop_reason（推理侧基础设施错误，非模型答错）：这些题的对错无信号意义，
-# 基线臂遇到时不得写入 BaselineCache（否则一次瞬时故障永久污染基线快照）。
-_INFRA_STOP_REASONS = frozenset({"error", "parse_error"})
-
-
 def _infra_question_ids_from_db(
     log: HarnessLog,
     run_id: str,
@@ -255,7 +255,7 @@ def _infra_question_ids_from_db(
     return {
         q.question_id
         for q in chunk
-        if rows.get(q.question_id, {}).get("stop_reason") in _INFRA_STOP_REASONS
+        if rows.get(q.question_id, {}).get("stop_reason") in INFRA_STOP_REASONS
     }