feat: enforce single-dimension counterfactual in AR distractor rules

tests/unit/test_ar_sub_pattern_counterfactual.py

@@ -0,0 +1,16 @@
+"""AR 6 个 SubPattern 的 distractor_rules 含单维反事实约束关键词。"""
+
+from app.question_gen.strategy_action_recognition import AR_SUB_PATTERNS
+
+_REQUIRED = ["真实", "单一维度"]  # 每个 distractor_rules 都需强调 grounded + 单维
+
+
+def test_all_sub_patterns_enforce_single_dimension_counterfactual():
+    for sp in AR_SUB_PATTERNS:
+        rules = sp.distractor_rules
+        assert "真实" in rules, sp.name  # 干扰项须真实发生
+        assert ("单一维度" in rules or "只在" in rules or "仅在" in rules), sp.name
+
+
+def test_sub_pattern_count_unchanged():
+    assert len(AR_SUB_PATTERNS) == 6