[Bug]: `special: untagged` breaks when entires previosly had tags

[mm12]

Checklist

• I am using an up-to-date version.
• I have read the documentation.
• I have searched existing issues.

TagStudio Version

Alpha 9.5.6

Operating System & Version

Win11 10.0.26200 Build 26200

Description

Searching special: untagged returns no results if all entries previously had tags, but all tags were deleted / removed.

Expected Behavior

special: untagged should return items that have no active tags.

Speculation on the root cause:
Deleted tags remain attached to items in the DB, causing the search to find no results for "items with 0 tags". The search should either check for active tags only, allow deleted tags, or the deleted tags should be removed from database items properly. If this is true, it would be in here, probably. I don't see anything deleting TagEntry items, so that might be it.

Steps to Reproduce

1. Have all items in a library inside (a) folder(s)
2. Convert folders -> tags. Optionally, manually add new tags to some items.
3. Delete the folder tag(s) with tag manager

Logs

No response