Releasing

A release is an annotated tag vX.Y.Z on main; there are no binaries.

1. .version in build.zig.zon names the new version.

2. CI on main is green, including the tools job that builds every tool against this commit.

3. COMPAT.md has a row for the version: the Zig version and the tool versions built on it.

4. Tag and push: git tag -a vX.Y.Z -m vX.Y.Z && git push origin vX.Y.Z.

5. Each tool moves to the tag in a commit of its own: zig fetch --save git+https://github.com/stackhands/zig-common#vX.Y.Z.