v0.5.1 — Fix install command and sync version metadata

What changed

Bug fixes only — no functional changes.

Install command corrected

The install command in CLAUDE.md was wrong. The correct two-step flow (which is what actually works) is now documented consistently across all files:

/plugin marketplace add hyhmrright/brooks-lint
/plugin install brooks-lint@brooks-lint-marketplace

Version metadata synced

plugin.json and marketplace.json were stuck at stale version numbers. Both now correctly reflect v0.5.1.

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Full feature set is unchanged from v0.5.0.