Add support for HTML entities in content docs

Leverage HtmlDocument for parsing.

Fixes #3

src/Epub/Content.cs

@@ -1,6 +1,7 @@
 using System.IO.Compression;
 using System.Xml;
 using System.Xml.Linq;
+using Devlooped.Web;
 
 namespace Devlooped.Epub;
 
@@ -35,11 +36,8 @@ public XDocument Open()
             throw new InvalidArchiveException(ThisAssembly.Strings.MissingContent(Href));
 
         using var stream = entry.Open();
-        using var reader = XmlReader
-            .Create(stream, new XmlReaderSettings { DtdProcessing = DtdProcessing.Ignore })
-            .IgnoreNamespaces();
 
-        return XDocument.Load(reader);
+        return HtmlDocument.Load(stream);
     }
 
     /// <summary>

src/Tests/PublicationTests.cs

@@ -29,6 +29,19 @@ public void CanOpen()
         Assert.NotNull(pub);
     }
 
+    [Fact]
+    public void CanReadContentFragments()
+    {
+        using var pub = Publication.Open(@"Samples/CCyC_Comentado_Tomo_II.epub");
+
+        Assert.NotNull(pub.Package.Navigation);
+
+        foreach (var nav in pub.Package.Navigation)
+        {
+            var content = nav.Open();
+        }
+    }
+
     [Fact]
     public void CanAccessPackageInformation()
     {