Got at least one data fetching method working; turns out, we can't use a patched LogicStack to get the data

Vendor/EmbedIO-3.5.2/Files/MappedResourceInfo.cs

@@ -0,0 +1,80 @@
+using System;
+
+namespace EmbedIO.Files
+{
+    /// <summary>
+    /// Contains information about a resource served via an <see cref="IFileProvider"/>.
+    /// </summary>
+    public sealed class MappedResourceInfo
+    {
+        private MappedResourceInfo(string path, string name, DateTime lastModifiedUtc, long length, string? contentType)
+        {
+            Path = path;
+            Name = name;
+            LastModifiedUtc = lastModifiedUtc;
+            Length = length;
+            ContentType = contentType;
+        }
+
+        /// <summary>
+        /// Gets a value indicating whether this instance represents a directory.
+        /// </summary>
+        public bool IsDirectory => ContentType == null;
+
+        /// <summary>
+        /// Gets a value indicating whether this instance represents a file.
+        /// </summary>
+        public bool IsFile => ContentType != null;
+
+        /// <summary>
+        /// Gets a unique, provider-specific path for the resource.
+        /// </summary>
+        public string Path { get; }
+
+        /// <summary>
+        /// Gets the name of the resource, as it would appear in a directory listing.
+        /// </summary>
+        public string Name { get; }
+
+        /// <summary>
+        /// Gets the UTC date and time of the last modification made to the resource.
+        /// </summary>
+        public DateTime LastModifiedUtc { get; }
+
+        /// <summary>
+        /// <para>If <see cref="IsDirectory"/> is <see langword="false"/>, gets the length of the file, expressed in bytes.</para>
+        /// <para>If <see cref="IsDirectory"/> is <see langword="true"/>, this property is always zero.</para>
+        /// </summary>
+        public long Length { get; }
+
+        /// <summary>
+        /// <para>If <see cref="IsDirectory"/> is <see langword="false"/>, gets a MIME type describing the kind of contents of the file.</para>
+        /// <para>If <see cref="IsDirectory"/> is <see langword="true"/>, this property is always <see langword="null"/>.</para>
+        /// </summary>
+        public string? ContentType { get; }
+
+        /// <summary>
+        /// Creates and returns a new instance of the <see cref="MappedResourceInfo"/> class,
+        /// representing a file.
+        /// </summary>
+        /// <param name="path">A unique, provider-specific path for the file.</param>
+        /// <param name="name">The name of the file, as it would appear in a directory listing.</param>
+        /// <param name="lastModifiedUtc">The UTC date and time of the last modification made to the file.</param>
+        /// <param name="size">The length of the file, expressed in bytes.</param>
+        /// <param name="contentType">A MIME type describing the kind of contents of the file.</param>
+        /// <returns>A newly-constructed instance of <see cref="MappedResourceInfo"/>.</returns>
+        public static MappedResourceInfo ForFile(string path, string name, DateTime lastModifiedUtc, long size, string contentType)
+            => new MappedResourceInfo(path, name, lastModifiedUtc, size, contentType ?? MimeType.Default);
+
+        /// <summary>
+        /// Creates and returns a new instance of the <see cref="MappedResourceInfo"/> class,
+        /// representing a directory.
+        /// </summary>
+        /// <param name="path">A unique, provider-specific path for the directory.</param>
+        /// <param name="name">The name of the directory, as it would appear in a directory listing.</param>
+        /// <param name="lastModifiedUtc">The UTC date and time of the last modification made to the directory.</param>
+        /// <returns>A newly-constructed instance of <see cref="MappedResourceInfo"/>.</returns>
+        public static MappedResourceInfo ForDirectory(string path, string name, DateTime lastModifiedUtc)
+            => new MappedResourceInfo(path, name, lastModifiedUtc, 0, null);
+    }
+}