Perception 2.0

[stephencelis]

Prep for the release of pointfreeco/swift-perception#141

[stephencelis]

@gemmakbarlow Just a heads up but when working on this PR SwiftSyntax v601 got pulled in temporarily, which is not library evolution-compatible, so I think our library evolution compatibility is a little tenuous and doesn't reflect the experience folks may have when trying to use our library. Not sure if you'd want to look into contributing a fix upstream to SwiftSyntax.

Also, while I was able to restore CI to an earlier pin of SwiftSyntax, we may have to disable library evolution CI on repos like this one in the future. We definitely aspire to make things as compatible as possible, but we unfortunately don't have the bandwidth to ensure that more edge case CI stays green.

[gemmakbarlow]

No worries, feel free to revert anything I added there. I probably don't have the bandwidth for the upstream fix either at the minute, but will take a look.

[stephencelis]

@gemmakbarlow Looks like it failed to pin after all 😕. I'm going to disable CI for now but whenever things are fixed in SwiftSyntax we will happily re-enable!