[pitch] Swift Benchmarking Infrastructure

if i may expand our horizons a bit, it would be much easier to write such tooling if we actually had complete, modern file system APIs.

swift-system just isn’t where it needs to be yet to support these kinds of use-cases. simple operations like writing a string to a file require fiddling around with ERRNO and unsafe buffer pointers, other fundamental operations like iterating a directory or kickstarting a subprocess aren’t implemented at all.

the FilePath APIs are clunky, emphasize pedantry over usability, and suffer from low ecosystem interoperability despite the stated goal of the API being to provide a common format for file paths.

libraries that only need the FilePath type definitions have to import and depend on the entire SystemPackage, which takes a long time to build (and should really be called SystemModule).

i've ended up having to write my own extensions to the package, as i'm sure many others have had to do as well. but my extensions only compile on linux, which means i can’t really use them in any serious public-facing libraries that need to maintain support for macOS and Windows, and cross-compile to devices.