Argument use detection is broken, and has been for a while

For example:

https://github.com/dotnet/fsharp/blob/d4a9f1356b119fa810cb32e56e0f90ab8698d82c/src/Compiler/Service/TransparentCompiler.fs#L2358

![Image](https://github.com/user-attachments/assets/771b4fc0-7267-4a03-ae53-69d2d50a30d9)

The argument `caret` is unused in the member, but the non-use is not detected by the compiler