<p>Relationship extraction is currently handled in the MediaLibrary synchronously for every new media item. It should be moved to its own importer block to take advantage of TPL and improve concurrency.</p>

<p>This should also allow the removal of the 2-pass import as the TPL network will import and commit files first and only later extract relations, allowing files to be available for playback early and removing the duplication caused by having to do 2 passes of every file.</p>