fix: 移动端新建会话关闭侧边栏 (#813)

src/views/chat/layout/sider/index.vue

@@ -18,6 +18,8 @@ const collapsed = computed(() => appStore.siderCollapsed)
 
 function handleAdd() {
   chatStore.addHistory({ title: 'New Chat', uuid: Date.now(), isEdit: false })
+  if (isMobile.value)
+    appStore.setSiderCollapsed(true)
 }
 
 function handleUpdateCollapsed() {