### The conformance matrix runs on Windows x86_64 again

- **`wai-conformance.yml`**'s cargo-class matrix has its `windows` leg back: the build, the
  library's tests, the fast-kernel steps in both profiles, the carriage, floor, `wai http`, agent,
  Create, world, staged, C ABI, signer-id and key-log tests, and every cargo-class corpus against
  its frozen hashes. A step of two commands chains them with `&&`, and a pwsh step of more than one
  sets `$PSNativeCommandUseErrorActionPreference`, so a command that fails stops its step there, as
  `sh -e` does on the other legs. That runner's `python3` is an alias that runs no Python, so the
  leg puts the host's own Python first on the PATH under that name. The corpus tools there are
  linked with an 8 MiB main-thread stack, as Linux gives one: `wai_pq_vectors`' debug build needs
  more than the 1 MiB Windows gives. Byte equality on Windows stays with `wai-byte-equality.yml`.
- **Line endings.** A checkout under `core.autocrlf`, as that runner's is, turned the corpora's LF
  into CR LF, and a corpus whose `verify` re-derives its `vectors.json` then found it changed:
  `.gitattributes` now keeps every `*-conformance/` tree, and the browser demo's byte copies of
  the `int_synth` corpus, unconverted. `catalogue`'s verb-list test reads the texts it compares as
  lines, and `cli_app`'s copies a project with the standard library rather than `cp`.