fix:DNS override server support is left blank by default (#3997)

* fix:DNS server support being left blank by default

* update logs

UPDATELOG.md

@@ -10,6 +10,7 @@
 - 修复导入订阅时非 http 协议链接被错误尝试导入
 - 修复切换节点后页面长时间 loading 及缓存过期导致的数据不同步问题
 - 修复将快捷键名称更名为 `Clash Verge`之后无法删除图标和无法删除注册表
+- 修复`DNS`覆写服务器支持默认留空
 
 ### ✨ 新增功能
 

src/components/setting/mods/dns-viewer.tsx

@@ -442,7 +442,7 @@ export const DnsViewer = forwardRef<DialogRef>((props, ref) => {
 
   // 解析列表字符串为数组
   const parseList = (str: string): string[] => {
-    if (!str) return [];
+    if (!str?.trim()) return [];
     return str
       .split(",")
       .map((item) => item.trim())
@@ -472,28 +472,17 @@ export const DnsViewer = forwardRef<DialogRef>((props, ref) => {
         ipcidr: parseList(values.fallbackIpcidr),
         domain: parseList(values.fallbackDomain),
       },
-    };
 
-    // 只在有值时添加其他可选字段
+      fallback: parseList(values.fallback),
-    if (values.fallback) {
+      "proxy-server-nameserver": parseList(values.proxyServerNameserver),
-      dnsConfig["fallback"] = parseList(values.fallback);
+      "direct-nameserver": parseList(values.directNameserver),
-    }
+    };
 
     const policy = parseNameserverPolicy(values.nameserverPolicy);
     if (Object.keys(policy).length > 0) {
       dnsConfig["nameserver-policy"] = policy;
     }
 
-    if (values.proxyServerNameserver) {
-      dnsConfig["proxy-server-nameserver"] = parseList(
-        values.proxyServerNameserver,
-      );
-    }
-
-    if (values.directNameserver) {
-      dnsConfig["direct-nameserver"] = parseList(values.directNameserver);
-    }
-
     return dnsConfig;
   };