Project file tree showing "loading..." forever

Two weeks ago, PyCharm was working fine. There were two updates, which I did, and now PyCharm just shows "loading..." in the file tree of one of my projects. The project is about 825KB in size.

I did allow the file indexing to complete, which also took a long time, and happens every time I load my project. This didn't happen previously.

Microsoft Defender has been configured to exclude my project paths.

I've deleted the .idea directory with no change. I've also invalidated the caches.

This is 2023.2 Professional Edition, build #PY-232.8660.197.  I don't recall what version was installed before.

The only thing that I can think that might be causing the issues is that I used VS Code to edit some of the files, as my PyCharm license had been expired. I don't see any extra files in my project, so I don't know how that could cause the issue.