http/https proxy (#7600)

* add http(s) proxy

* Add front-end translation

* fix ui description

* For linux platform, add rustls support

* fix: Fix the proxy address test function.

* add: Added default prompts for agency agreement and some multi-language translations

* add: Http proxy request client

* fix: add async http proxy func and format the code

* add: Preliminary support for flutter front-end calling rust back-end http request

* Optimize HTTP calls

* Optimize HTTP calls

* fix: Optimize HTTP requests, refine translations, and fix dependencies

flutter/lib/desktop/pages/desktop_setting_page.dart

@@ -1117,7 +1117,7 @@ class _NetworkState extends State<_Network> with AutomaticKeepAliveClientMixin {
                 child: Column(children: [
                   server(enabled),
                   _Card(title: 'Proxy', children: [
-                    _Button('Socks5 Proxy', changeSocks5Proxy,
+                    _Button('Socks5/Http(s) Proxy', changeSocks5Proxy,
                         enabled: enabled),
                   ]),
                 ]),
@@ -2047,7 +2047,7 @@ void changeSocks5Proxy() async {
     }
 
     return CustomAlertDialog(
-      title: Text(translate('Socks5 Proxy')),
+      title: Text(translate('Socks5/Http(s) Proxy')),
       content: ConstrainedBox(
         constraints: const BoxConstraints(minWidth: 500),
         child: Column(
@@ -2064,7 +2064,9 @@ void changeSocks5Proxy() async {
                 Expanded(
                   child: TextField(
                     decoration: InputDecoration(
-                        errorText: proxyMsg.isNotEmpty ? proxyMsg : null),
+                        errorText: proxyMsg.isNotEmpty ? proxyMsg : null,
+                        hintText: translate('Default protocol and port are Socks5 and 1080'),
+                    ),
                     controller: proxyController,
                     autofocus: true,
                   ),