[WIP] Fix VorbisComment tag handling for FLAC files

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>FLAC set the VorbisComment as tag incorrectly</issue_title>
<issue_description>

TagLibSharp2/src/TagLibSharp2/Core/MediaFile.cs

Line 389 in 527b7fb

return MediaFileResult.Success (result.File!, result.File!.VorbisComment, MediaFormat.Flac);

VorbisComment is being used as tag and cause the issue.
For example, for flac file, property Pictures contains 1 element in the MediaFileResult.File but not in the MediaFileResult.Tag</issue_description>

<agent_instructions>Create a fix and unit tests for this issue</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes FLAC set the VorbisComment as tag incorrectly #6

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.23%. Comparing base (527b7fb) to head (57763b7).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #10   +/-   ##
=======================================
  Coverage   83.23%   83.23%           
=======================================
  Files          95       95           
  Lines       12362    12362           
  Branches     2549     2549           
=======================================
  Hits        10289    10289           
  Misses       1257     1257           
  Partials      816      816           

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