fix(deepresearch): 修复背景调查节点的结果列表大小比较逻辑- 将不等修正为相等- 确保结果列表与查询列表的大小一致，避免潜在的索引越界问题

Author: HunterPorter

spring-ai-alibaba-deepresearch/src/main/java/com/alibaba/cloud/ai/example/deepresearch/node/BackgroundInvestigationNode.java

@@ -101,7 +101,7 @@ public Map<String, Object> apply(OverAllState state) throws Exception {
 		resultMap.put("site_information", resultsList);
 
 		List<String> backgroundResults = new ArrayList<>();
-		assert resultsList.size() != queries.size();
+		assert resultsList.size() == queries.size();
 
 		for (int i = 0; i < resultsList.size(); i++) {
 			List<Map<String, String>> searchResults = resultsList.get(i);