feat: add Homebrew distribution and automated versioning

[blackaxgit]

Summary

• Homebrew tap auto-update: Add update-homebrew job to release workflow that generates and pushes a Homebrew formula to blackaxgit/homebrew-clx after each stable release
• Automated versioning with release-plz: Add workflow that creates Release PRs with version bumps + changelogs from conventional commits. On merge, creates git tag that triggers the existing release pipeline
• README: Add "Quick Install" Homebrew section, update architecture note to include Intel

Homebrew Tap (update-homebrew job)

push tag → build (ARM + Intel) → release → update-homebrew → tap updated

The update-homebrew job downloads SHA256 checksums from the release, generates Formula/clx.rb with architecture-conditional URLs, and pushes to the tap repo. Skips pre-releases.

User install: brew tap blackaxgit/clx && brew install clx

Automated Versioning (release-plz)

merge PR (feat:/fix:) → Release PR auto-created → merge it → tag → build → release → homebrew

Config highlights:

• publish = false / git_only = true — binary-only, no crates.io
• git_release_enable = false — avoids duplicate GitHub Releases (release.yml handles it)
• git_tag_name = "v{{ version }}" — matches release.yml trigger
• version_group = "clx" — all 4 crates version together
• release_always = false — only releases when Release PR is merged

Requires: RELEASE_PLZ_TOKEN secret (Fine-Grained PAT with Contents + PRs read/write). Tags created by GITHUB_TOKEN cannot trigger downstream workflows.

Prerequisites (manual)

• Create blackaxgit/homebrew-clx repo
• Add HOMEBREW_TAP_TOKEN secret
• Add RELEASE_PLZ_TOKEN secret
• Create baseline tag v0.1.0 after merge

Test plan

• YAML validated (ruby parser)
• TOML validated (python tomllib)
• Heredoc formula generation tested locally
• All 671 workspace tests pass
• 0 clippy warnings
• End-to-end: create baseline tag, merge feature PR, verify Release PR created

🤖 Generated with Claude Code