fix: default to udp://1.1.1.1 DNS (DoT fails silently, breaks all proxy connections)

config_builder.py

@@ -23,7 +23,7 @@ def make_dns_server(addr_str: str) -> Dict[str, Any]:
     Supports: udp://host:port, tls://host(:port), https://host(:port), bare IP/hostname.
 
     Args:
-        addr_str: DNS server address string (e.g. "tls://8.8.8.8", "udp://1.1.1.1:53").
+        addr_str: DNS server address string (e.g. "udp://1.1.1.1", "tls://8.8.8.8").
 
     Returns:
         Dictionary compatible with sing-box DNS server schema.
@@ -56,7 +56,7 @@ def build_singbox_config(
     socks_port: int = 1080,
     socks_user: str = "",
     socks_pass: str = "",
-    dns_server: str = "tls://8.8.8.8",
+    dns_server: str = "udp://1.1.1.1",
     log_level: str = "info",
 ) -> Dict[str, Any]:
     """Build a complete sing-box JSON configuration.