Uploads are immutable, so a malformed archive cannot be replaced at its
version path. verify-package checks the zip has one top-level directory,
carries lua/, plugin/, doc/ and README.md, and leaks no dev or CI files.
- add lua modules for spec parsing, lock state, fs helpers and the installer
- add ArtiPackSync/ArtiPackClean/ArtiPackList commands and help doc
- add headless nvim test harness and specs
- add make test/lint/fmt/pre-commit and patch/minor/major bump targets
- add woodpecker test, lint and pre-commit pipelines