feat(sub): opt-in dns and sniffer from remote Clash rules (#6868)

Public Mihomo templates ship rules, rule-providers and proxy-groups together
with a dns block those rules depend on (fake-ip ranges, nameserver policy).
Pasting a template inline keeps its dns, but pointing the global routing rules
at its URL dropped it, so URL users had to give up auto-refresh to keep it.

A new switch, subClashRemoteDNS (off by default), also takes the remote dns and
sniffer maps. It is opt-in because a remote dns block decides where clients send
every lookup. A malformed dns or sniffer value is skipped, not the whole template.
The component-test teardown now outlasts AntD Form's 10ms error debounce, which
otherwise fired after jsdom was gone.

internal/web/service/setting.go

@@ -186,6 +186,7 @@ var defaultValueMap = map[string]string{
 	"subClashURI":                 "",
 	"subClashEnableRouting":       "false",
 	"subClashRules":               "",
+	"subClashRemoteDNS":           "false",
 	"subJsonMux":                  "",
 	"subJsonRules":                "",
 	"subJsonRoutingRules":         "",
@@ -1241,6 +1242,10 @@ func (s *SettingService) GetSubClashRules() (string, error) {
 	return s.getString("subClashRules")
 }
 
+func (s *SettingService) GetSubClashRemoteDNS() (bool, error) {
+	return s.getBool("subClashRemoteDNS")
+}
+
 func (s *SettingService) GetSubJsonMux() (string, error) {
 	return s.getString("subJsonMux")
 }