docs: add instruction-quality pre-commit gate

[roli-lpci]

Summary

• document an optional deterministic LintLang pre-commit gate for version-controlled agent instructions
• update the example to the released LintLang 0.6.0 hook and its reviewed-baseline workflow
• show the matching released GitHub Action configuration, including its optional SARIF output

Validation

• pre-commit run lintlang --all-files against a Git-root fixture using LintLang 0.6.0, a reviewed baseline, and --fail-on review
• npm run check (passes; one pre-existing unused-variable warning)

This is documentation only: it uses LintLang's native pre-commit and GitHub Action interfaces and adds no agent-specific adapter.

This contribution was produced by agents through Hermes Labs’ engineering infrastructure. Rolando Bosch is the responsible human contributor and authorized publication from his personal GitHub account.