feat: Add NordVPN NordLynx (WireGuard) integration (#3827)

* feat: Add NordVPN NordLynx (WireGuard) integration with dedicated UI and backend services.

* remove limit=10 to get all servers

* feat: add city selector to NordVPN modal

* feat: auto-select best server on country/city change

* feat: simplify filter logic and enforce > 7% load

* fix

---------

Co-authored-by: Sanaei <ho3ein.sanaei@gmail.com>

web/service/setting.go

@@ -80,6 +80,7 @@ var defaultValueMap = map[string]string{
 	"subJsonRules":                "",
 	"datepicker":                  "gregorian",
 	"warp":                        "",
+	"nord":                        "",
 	"externalTrafficInformEnable": "false",
 	"externalTrafficInformURI":    "",
 	"xrayOutboundTestUrl":         "https://www.google.com/generate_204",
@@ -598,6 +599,14 @@ func (s *SettingService) SetWarp(data string) error {
 	return s.setString("warp", data)
 }
 
+func (s *SettingService) GetNord() (string, error) {
+	return s.getString("nord")
+}
+
+func (s *SettingService) SetNord(data string) error {
+	return s.setString("nord", data)
+}
+
 func (s *SettingService) GetExternalTrafficInformEnable() (bool, error) {
 	return s.getBool("externalTrafficInformEnable")
 }