Adds PressAdvantageClient API wrapper and submit_press_release tool that
posts finished press releases to PA as drafts. Auto-constructs SEO links
(brand+keyword → IMSURL, company name → SocialURL/GBP/homepage) with
fuzzy anchor matching and warnings when phrases can't be found. The PR
writing prompt now requests anchor text phrases and validates them after
generation.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>