refactor: h3 for doh

config/config.go

@@ -157,6 +157,7 @@ type Config struct {
 
 type RawDNS struct {
 	Enable                bool              `yaml:"enable"`
+	PreferH3              bool              `yaml:"prefer-h3"`
 	IPv6                  bool              `yaml:"ipv6"`
 	UseHosts              bool              `yaml:"use-hosts"`
 	NameServer            []string          `yaml:"nameserver"`
@@ -767,6 +768,7 @@ func parseDNS(rawCfg *RawConfig, hosts *trie.DomainTrie[netip.Addr], rules []C.R
 	dnsCfg := &DNS{
 		Enable:       cfg.Enable,
 		Listen:       cfg.Listen,
+		PreferH3:     cfg.PreferH3,
 		IPv6:         cfg.IPv6,
 		EnhancedMode: cfg.EnhancedMode,
 		FallbackFilter: FallbackFilter{