refactor(uakino): replace Http.Get with custom GetString method

Implement a new GetString method using HttpClient for better control over
HTTP requests including proxy handling, SSL validation, and timeout management.
This replaces the previous Http.Get calls throughout the UAKino module to
standardize request handling and improve reliability.

UAKino/UAKinoInvoke.cs

@@ -1,8 +1,12 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Net;
+using System.Net.Http;
+using System.Security.Authentication;
 using System.Text.Json;
 using System.Text.RegularExpressions;
+using System.Threading;
 using System.Threading.Tasks;
 using System.Web;
 using HtmlAgilityPack;
@@ -62,7 +66,7 @@ namespace UAKino
                     };
 
                     _onLog?.Invoke($"UAKino search: {searchUrl}");
-                    string html = await Http.Get(searchUrl, headers: headers, proxy: _proxyManager.Get());
+                    string html = await GetString(searchUrl, headers);
                     if (string.IsNullOrEmpty(html))
                         continue;
 
@@ -147,7 +151,7 @@ namespace UAKino
             try
             {
                 _onLog?.Invoke($"UAKino playlist: {url}");
-                string payload = await Http.Get(url, headers: headers, proxy: _proxyManager.Get());
+                string payload = await GetString(url, headers);
                 if (string.IsNullOrEmpty(payload))
                     return null;
 
@@ -189,7 +193,7 @@ namespace UAKino
             try
             {
                 _onLog?.Invoke($"UAKino movie page: {href}");
-                string html = await Http.Get(href, headers: headers, proxy: _proxyManager.Get());
+                string html = await GetString(href, headers);
                 if (string.IsNullOrEmpty(html))
                     return null;
 
@@ -232,7 +236,7 @@ namespace UAKino
             try
             {
                 _onLog?.Invoke($"UAKino parse player: {url}");
-                string html = await Http.Get(url, headers: headers, proxy: _proxyManager.Get());
+                string html = await GetString(url, headers);
                 if (string.IsNullOrEmpty(html))
                     return null;
 
@@ -253,6 +257,45 @@ namespace UAKino
             }
         }
 
+        private async Task<string> GetString(string url, List<HeadersModel> headers, int timeoutSeconds = 15)
+        {
+            var handler = new HttpClientHandler
+            {
+                AllowAutoRedirect = true,
+                AutomaticDecompression = DecompressionMethods.Brotli | DecompressionMethods.GZip | DecompressionMethods.Deflate,
+                SslProtocols = SslProtocols.Tls12 | SslProtocols.Tls13
+            };
+
+            handler.ServerCertificateCustomValidationCallback += (sender, cert, chain, sslPolicyErrors) => true;
+
+            var proxy = _proxyManager.Get();
+            if (proxy != null)
+            {
+                handler.UseProxy = true;
+                handler.Proxy = proxy;
+            }
+            else
+            {
+                handler.UseProxy = false;
+            }
+
+            using var client = new HttpClient(handler);
+            using var req = new HttpRequestMessage(HttpMethod.Get, url);
+
+            if (headers != null)
+            {
+                foreach (var h in headers)
+                    req.Headers.TryAddWithoutValidation(h.name, h.val);
+            }
+
+            using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(Math.Max(5, timeoutSeconds)));
+            using var response = await client.SendAsync(req, cts.Token).ConfigureAwait(false);
+            if (!response.IsSuccessStatusCode)
+                return null;
+
+            return await response.Content.ReadAsStringAsync(cts.Token).ConfigureAwait(false);
+        }
+
         private List<PlaylistItem> ParsePlaylistHtml(string html)
         {
             var items = new List<PlaylistItem>();