Let it loose on a large Library, and fails miserably.

I have an old library, 30y of collecting, backing up, sharing libraries, etc..
It's a complete mishmash of stuff. Though all files work and play just fine, cleanup is a constant fail.

I had hoped to let it loose on the entire thing, but.. no matter the changes to the config, it keeps deadlocking and freezing ...
Even when settings things like:
- ignore_unreadable: yes
- threaded: no
- mblookup: no
- write: no
- ui:
strict: no
- chroma:
auto: no
skip_failures: yes
etc..
I started with a full loadout of do everything, and turning things off as we go, step by step.
But, beets just gets deadlocked by one of the functions in the background each time.
Making it, quite useless ..

Out of 1TB, it was able to process 202 files, before every time freezing.
No output, no error, no more log, no more changes, just... stuck.
Who cares that an MP3 tag is corrupted or whatever, keep going.

I was quite hoping for, after such a long time, a library scan and cleanup.
But, no... so far just.. a waste of time

Start by reproducing the freeze during a large library scan with the reported configuration, including ignore_unreadable, threaded, mblookup, write, ui.strict, and chroma settings. The issue names no source file or test, so identify which background operation stops progress and capture logs or a minimal failing library. Done means the scan continues past the failure or reports an actionable error instead of freezing.

Written by the indexing model from the issue text.