feat: 新增 Hosts 写入功能，通过预设的干净 DNS 获取ip 并 写入 hosts 文件

lib/common/helper/system_helper.dart

@@ -257,4 +257,10 @@ foreach ($adapter in $adapterMemory) {
     await Process.run(
         SystemHelper.powershellPath, ["explorer.exe", "/select,\"$path\""]);
   }
+
+  static String getHostsFilePath() {
+    final envVars = Platform.environment;
+    final systemRoot = envVars["SYSTEMROOT"];
+    return "$systemRoot\\System32\\drivers\\etc\\hosts";
+  }
 }

lib/common/io/rs_http.dart

@@ -51,13 +51,20 @@ class RSHttp {
   }
 
   static Future<RustHttpResponse> head(String url,
-      {Map<String, String>? headers}) async {
+      {Map<String, String>? headers, String? withIpAddress}) async {
     final r = await rust_http.fetch(
-        method: MyMethod.head, url: url, headers: headers);
+        method: MyMethod.head,
+        url: url,
+        headers: headers,
+        withIpAddress: withIpAddress);
     return r;
   }
 
   static Future<List<String>> dnsLookupTxt(String host) async {
     return await rust_http.dnsLookupTxt(host: host);
   }
+
+  static Future<List<String>> dnsLookupIps(String host) async {
+    return await rust_http.dnsLookupIps(host: host);
+  }
 }

lib/common/utils/async.dart

@@ -8,7 +8,7 @@ extension AsyncError on Future {
       return await this;
     } catch (e) {
       dPrint("unwrap error:$e");
-      if (context != null) {
+      if (context != null && context.mounted) {
         showToast(context, "出现错误: $e");
       }
       return null;