Refactor ReCClient to use IHttpClientFactory

Updated ReCClient to use IHttpClientFactory for improved
resource management and testability. Added package
references for `Microsoft.Extensions.Http`, `System.Net.Http`,
and `System.Text.Json` to support HTTP client functionality
and JSON serialization. Included `System.Xml.Linq` for
potential XML-related operations. Updated constructor logic
to create `HttpClient` instances via the factory pattern.

src/ReC.Client/ReC.Client.csproj

@@ -10,6 +10,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
+	  <PackageReference Include="Microsoft.Extensions.Http" Version="10.0.0" />
 	  <PackageReference Include="System.Net.Http" Version="4.3.4" />
 	  <PackageReference Include="System.Text.Json" Version="9.0.11" />
 	</ItemGroup>

src/ReC.Client/ReCClient.cs

@@ -1,4 +1,6 @@
 using System.Text.Json;
+using System.Xml.Linq;
+
 #if NETFRAMEWORK
 using System;
 using System.Net.Http;
@@ -14,9 +16,9 @@ namespace ReC.Client
         private readonly HttpClient _http;
         private readonly JsonSerializerOptions _jsonOptions = new JsonSerializerOptions() { PropertyNameCaseInsensitive = true };
 
-        public ReCClient(HttpClient http)
+        public ReCClient(IHttpClientFactory httpClientFactory)
         {
-            _http = http ?? throw new ArgumentNullException(nameof(http));
+            _http = httpClientFactory.CreateClient();
         }
 
         /// <summary>