Update .build.yml

Document expected error in CI

Fix typo in `make-release` CI target

Fix build

Swap to alpine build image

Debian stable's rustc is too old lmao.

Fix .build.yml dependencies

Add sourcehut CI

Explicitly qualify `clap::Parser` derive

Allow `0` as a valid value for `--number`

This simplifies the code a fair bit, and there was no good reason
for that limitation in the first place.

Update doc comments + help output

Update make `clean` target

Fix more typos

Fix links in README

Bump version to 1.0.0

Add CHANGELOG file

Fix clippy warnings

Wrap man page source to 80 columns

Update README

Add Makefile

Add man page