fix: 修复 trigger.operator null + 添加覆盖反馈重试 - Closes #22, Closes #21

#22: _normalize_rule 补充 trigger 级别 operator (AND/OR) 默认值
#21: step1 验证失败时自动生成覆盖反馈并重试一轮
#22: step2 过滤空规则片段，避免污染下游

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

skills/ir_generation_skill/step2_ir_extraction.py

@@ -497,6 +497,13 @@ def main():
     print(f"\n[2/3] 逐单元提取 IR 规则...")
     fragments = extract_all_rules(semantic_index, doc)
 
+    # Filter out fragments with empty rules (LLM extraction failures)
+    empty_units = [f["unit_id"] for f in fragments
+                   if not f.get("rules") and not f.get("error")]
+    if empty_units:
+        print(f"  [WARN] {len(empty_units)} 个单元规则为空，已过滤: {empty_units}")
+    fragments = [f for f in fragments if f.get("rules") or f.get("error")]
+
     # 3. Save
     print(f"\n[3/3] 保存 IR 片段...")
     config.save_json(fragments, config.IR_FRAGMENTS_JSON)