Refactor for clarity; add docs and .editorconfig

Refactored code to consistently use `this.` for instance members, improving clarity and maintainability. Added XML documentation comments to multiple methods and properties for better API documentation. Streamlined `FfProbeKeyframeExtractor` logic and enhanced EBML parsing code with comments and style improvements. Introduced a new `.editorconfig` to disable legacy StyleCop and IDisposableAnalyzers rules. Updated binary files, assembly info, and NuGet cache files due to rebuilds and dependency changes. No functional changes were made.

MediaBrowser.Controller/Entities/Audio/Audio.cs

@@ -142,7 +142,7 @@ namespace MediaBrowser.Controller.Entities.Audio
 
         public SongInfo GetLookupInfo()
         {
-            var info = GetItemLookupInfo<SongInfo>();
+            var info = this.GetItemLookupInfo<SongInfo>();
 
             info.AlbumArtists = AlbumArtists;
             info.Album = Album;

MediaBrowser.Controller/Entities/AudioBook.cs

@@ -31,36 +31,64 @@ namespace MediaBrowser.Controller.Entities
         [JsonIgnore]
         public Guid SeriesId { get; set; }
 
+        /// <summary>
+        /// Finds the series sort name.
+        /// </summary>
+        /// <returns>The series sort name.</returns>
         public string FindSeriesSortName()
         {
-            return SeriesName;
+            return this.SeriesName;
         }
 
+        /// <summary>
+        /// Finds the series name.
+        /// </summary>
+        /// <returns>The series name.</returns>
         public string FindSeriesName()
         {
-            return SeriesName;
+            return this.SeriesName;
         }
 
+        /// <summary>
+        /// Finds the series presentation unique key.
+        /// </summary>
+        /// <returns>The series presentation unique key.</returns>
         public string FindSeriesPresentationUniqueKey()
         {
-            return SeriesPresentationUniqueKey;
+            return this.SeriesPresentationUniqueKey;
         }
 
+        /// <summary>
+        /// Gets the default primary image aspect ratio.
+        /// </summary>
+        /// <returns>The default primary image aspect ratio.</returns>
         public override double GetDefaultPrimaryImageAspectRatio()
         {
             return 0;
         }
 
+        /// <summary>
+        /// Finds the series identifier.
+        /// </summary>
+        /// <returns>The series identifier.</returns>
         public Guid FindSeriesId()
         {
-            return SeriesId;
+            return this.SeriesId;
         }
 
+        /// <summary>
+        /// Determines whether this audiobook can be downloaded.
+        /// </summary>
+        /// <returns>True if downloadable; otherwise, false.</returns>
         public override bool CanDownload()
         {
-            return IsFileProtocol;
+            return this.IsFileProtocol;
         }
 
+        /// <summary>
+        /// Gets the unrated type for blocking purposes.
+        /// </summary>
+        /// <returns>The unrated item type.</returns>
         public override UnratedItem GetBlockUnratedType()
         {
             return UnratedItem.Book;