* Support sing-box 1.14
* Unified format
* Support parallel dns
* Add `optimistic DNS caching` support
* Try fix serial multi DNS
* Add HttpClient support
sing-box requires realm.server_url as a full URL (https://host:port).
Bare host:port caused "missing host in realm server_url" on import.
Also forward stun_servers and clear ResolveRealm success message.
Fixes#9635
Move many model classes into new sub-namespaces (ServiceLib.Models.CoreConfigs, ServiceLib.Models.Configs, ServiceLib.Models.Dto, ServiceLib.Models.Entities). Update GlobalUsings in ServiceLib, v2rayN.Desktop, v2rayN and add a tests GlobalUsings file to reference the new namespaces. Adjust static using directives in ClashApiManager and ClashProxiesViewModel to use ServiceLib.Models.Dto. This is a reorganization/rename of files and namespaces with no functional changes.