[ Feature Request ] remove sub title metadata too

When using "remove metadata" will be removed metadata of video, all sound tracks and file metadata. Sub title does use metadata too, but not not are removed too.
Nvencc use the command --sub-metadata 1?clear to remove subtitle metadata.
However if source file has subtitle and the user had selected to not "preserve" waiting the enconded file without subtitle if using command "--sub-metadata 1?clear" will save the subtitle in enconded file.
Have a nice week.

The issue does not name a file, test, or entry point. Start by tracing the existing “remove metadata” option and subtitle-preservation handling; confirm the expected behavior for subtitle metadata removal versus omitting subtitles, then add coverage for both paths.

Written by the indexing model from the issue text.