Add support for VobSub subtitle streams (#16552)

* Add support for VobSub subtitle streams

* update logic to determine separate extraction for VobSub subtitles

* simplify VobSub extraction logic and fix ffmpeg command

* Match `ExtractAllExtractableSubtitlesMKS` with `ExtractAllExtractableSubtitlesInternal` Matroska's VobSub option

* Add a comments clarify why MKS was used, and remove the redundant VobSub extension branch

* remove redundant VobSub format check

* fix type errors

Emby.Server.Implementations/Library/MediaSourceManager.cs

@@ -127,6 +127,11 @@ namespace Emby.Server.Implementations.Library
                 return true;
             }
 
+            if (stream.IsVobSubSubtitleStream)
+            {
+                return true;
+            }
+
             return false;
         }