Enable concurrency dns query

app/src/main/java/io/nekohasekai/sagernet/fmt/ConfigBuilder.kt

@@ -196,6 +196,7 @@ fun buildV2RayConfig(
                 DnsObject.StringOrServerObject().apply {
                     valueY = DnsObject.ServerObject().apply {
                         address = it
+                        concurrency = true
                     }
                 }
             })
@@ -1241,6 +1242,7 @@ fun buildV2RayConfig(
                         address = if (!it.contains("://") && it != "localhost") "udp+local://$it" else it
                         domains = bypassDomain.toList()
                         skipFallback = true
+                        concurrency = true
                     }
                 }
             })

app/src/main/java/io/nekohasekai/sagernet/fmt/v2ray/V2RayConfig.java

@@ -70,6 +70,7 @@ public class V2RayConfig {
             public Boolean skipFallback;
             public List<String> domains;
             public List<String> expectIPs;
+            public boolean concurrency;
 
         }