fix(identity): 重构 agent 命名检测正则 — 覆盖"名称改为小芳"等表达

detectAgentNameSuggestion 从固定正则改为 trigger+extract 两步法，
10 个 trigger 模式覆盖中文/英文常见命名表达，stopWords 过滤误匹配。
同时修复 streamStore content 类型处理和 RightPanel 重复事件监听。

desktop/src/store/chat/streamStore.ts

@@ -386,8 +386,9 @@ function createCompleteHandler(
             log.warn('Failed to persist detected userName:', e);
           }
         }
-        // Detect agent name change (e.g. "叫你小马", "以后叫你小马")
-        const detectedAgentName = lastUserMsg ? detectAgentNameSuggestion(lastUserMsg.content) : undefined;
+        // Detect agent name change (e.g. "叫你小马", "以后叫你小马", "你就叫小马吧")
+        const lastContent = typeof lastUserMsg?.content === 'string' ? lastUserMsg.content : '';
+        const detectedAgentName = lastContent ? detectAgentNameSuggestion(lastContent) : undefined;
         if (detectedAgentName && agentId) {
           try {
             const { useAgentStore } = await import('../agentStore');