fix: 优化用户信息展示

src/layouts/BasicLayout.module.less

@@ -62,7 +62,7 @@
     align-items: center;
   }
 
-  .userPhone {
+  .displayName {
     font-size: 14px;
     color: rgba(0, 0, 0, 0.65);
   }

src/layouts/BasicLayout.tsx

@@ -79,6 +79,7 @@ export default defineComponent({
 
     const { menuItems } = useMenuStore();
     const { phone, nickname } = useUserStore();
+    const displayName = computed(() => nickname.value || phone.value);
     const {
       tabs,
       cachedViews,
@@ -232,7 +233,7 @@ export default defineComponent({
 
               {/* 右侧: 账号信息 + 退出 */}
               <div class={styles.headerRight}>
-                <span class={styles.userPhone}>{nickname.value}</span>
+                <span class={styles.displayName}>{displayName.value}</span>
                 <Dropdown trigger={['hover']} placement="bottomLeft">
                   {{
                     default: () => <img src={logoutSvg} class={styles.logoutIcon} />,