v1.0.0

First release, by Louis Wright.

• Canonical checks: missing, multiple, invalid, relative, outside <head>, tracking parameters/fragments, og:url and Link header mismatches.
• Canonical targets: must exist in the build, not be an error page or meta-refresh stub, not be noindex, and not chain to another canonical; cross-host/protocol canonicals flagged unless allowed.
• noindex + cross-page canonical conflict.
• hreflang: code validation (ISO 639-1 / ISO 3166-1 / UN M.49 / x-default), self-reference, reciprocal return links, duplicate codes, relative hrefs, missing/noindex/non-canonical alternates, hreflang on non-canonical pages, x-default and <html lang> agreement.
• Text/JSON/SARIF/Markdown output, --fail-on, exit codes 0/1/2, allowlist with expiry, severity overrides.
• Composite GitHub Action with job summary.