Add a `claude-code` skill for generating commit msgs
matching `tractor`'s style, plus a companion style guide
derived from analysis of 500 repo commits.
Deats,
- `SKILL.md` defines the `commit-msg` skill with YAML
frontmatter, outlining the generation process, formatting
rules, and footer conventions.
- `style-guide-reference.md` documents verb frequencies,
backtick usage patterns, section markers, abbreviations,
and tone from historical commit analysis.
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Gud Boi
20896bfbab