feat: loosen multi_true gate to qualifier-scoped correctness

tests/unit/test_gate_multi_true_rubric.py

@@ -0,0 +1,13 @@
+"""multi_true rubric 已松绑为题干限定判据。"""
+
+from pathlib import Path
+
+_PROMPT = Path(__file__).resolve().parents[2] / "store" / "prompts" / "question_gen" / "gate_multi_true.md"
+
+
+def test_rubric_uses_qualifier_constraint():
+    text = _PROMPT.read_text(encoding="utf-8")
+    # 新 rubric 必须提到"题干限定下同时为真才 fail"（qualifier / under the question's constraints）
+    assert "under the question" in text.lower() or "qualifier" in text.lower()
+    # 必须显式放行"有局部真实证据但在限定下为假"的干扰项
+    assert "partial" in text.lower() or "locally" in text.lower()