Restore perception checking tests on macOS

[pyrtsa]

There seem to have been a recent change to the macOS toolchain where both Testing.framework and libXCTestSwiftSupport.dylib got built against macOS 14.0 runtime.

As a result, swift test (unless run with both --disable-xctest and --disable-swift-testing) forces the test target to build with arm64-apple-macosx14.0 as the minimum deployment target, no matter which lower value the Package.swift file has in its platforms array.

This PR adds deprecation annotations on the affected tests, silencing the deprecation warnings, and also skips the failing tests unless the test target it proven to built against an older deployment target¹. I set swift test to build against the older deployment target by passing -target arm64-apple-macosx13.0 to swiftc in ci.yml. This seems to work, but YMMV.

There are two new linker warnings when running tests like this, but I think we can live with them:

ld: warning: building for macOS-13.0, but linking with dylib '@rpath/Testing.framework/Versions/A/Testing' which was built for newer version 14.0
ld: warning: building for macOS-13.0, but linking with dylib '@rpath/libXCTestSwiftSupport.dylib' which was built for newer version 14.0

With these changes, I think we can restore unit tests in ci.yml and also include Xcode 26.0.

Footnotes

1. This in turn is a little hack with @_disfavoredOverload, intentionally symmetrical to what the library already does to hide the backports. ↩

[stephencelis]

Good finds, thanks for diving into this!