Checking whether JetBrains Fleet can be used for visionOS app development
JetBrains previously released a product called AppCode. It was an IDE for iOS and macOS, but sales apparently ended on December 14, 2022.
Currently, JetBrains Fleet is officially presented as the alternative product.
In practice, Fleet can load Swift files and provide coding support.
When I loaded a local iOS project, the tutorial Landscape project, I was able to build it.

In this case, I could choose iOS as the simulator target during build, and the build worked.

However, when trying to build a visionOS project, a message appeared saying that the simulator could not be found. Even in this state, Swift support works, so if you only want to code, you can still work.

After looking into it, it seems that building for visionOS is probably not possible at the moment. I found a ticket that appears related, so I will link it here.
Fleet is fairly pleasant to use, so I will keep watching its progress while dreaming of being able to develop visionOS apps with it someday.