clippy all codes (#1214)

1. clippy code
2. add fmt and clippy check in ci

easytier/src/instance/dns_server/server_instance.rs

@@ -70,6 +70,20 @@ pub(super) struct MagicDnsServerInstanceData {
 }
 
 impl MagicDnsServerInstanceData {
+    fn is_valid_subdomain_label(s: &str) -> bool {
+        let s = s.trim();
+
+        // 长度检查：1-63 个字符
+        if s.is_empty() || s.len() > 63 {
+            return false;
+        }
+
+        // 检查每个字符是否合法，并确保不以 '-' 开头或结尾
+        s.chars().all(|c| matches!(c, 'a'..='z' | '0'..='9' | '-'))
+            && !s.starts_with('-')
+            && !s.ends_with('-')
+    }
+
     pub async fn update_dns_records<'a, T: Iterator<Item = &'a Route>>(
         &self,
         routes: T,
@@ -81,6 +95,11 @@ impl MagicDnsServerInstanceData {
                 continue;
             }
 
+            // check host name valid for dns
+            if !Self::is_valid_subdomain_label(&route.hostname) {
+                continue;
+            }
+
             let Some(ipv4_addr) = route.ipv4_addr.unwrap_or_default().address else {
                 continue;
             };
@@ -432,7 +451,7 @@ impl MagicDnsServerInstance {
         if !self.tun_inet.contains(&self.data.fake_ip) && self.data.tun_dev.is_some() {
             let ifcfg = IfConfiger {};
             let _ = ifcfg
-                .remove_ipv4_route(&self.data.tun_dev.as_ref().unwrap(), self.data.fake_ip, 32)
+                .remove_ipv4_route(self.data.tun_dev.as_ref().unwrap(), self.data.fake_ip, 32)
                 .await;
         }