Clarify ATS score metrics guide from Search Console evidence

[sarthakagrawal927]

Google Search Console shows the ATS score guide earning 72 impressions for ats metrics at average position 77.2. Improve the existing guide without keyword stuffing: distinguish third-party match scores from employer ATS metrics, remove unsupported universal threshold claims, add concrete candidate-facing metrics, and preserve the current RolePatch CTA.

Acceptance criteria:

• metadata describes ATS scores and metrics accurately
• guide states there is no universal ATS score or pass threshold
• guide explains actionable match/parse metrics for candidates
• public-surface description stays aligned
• existing checks pass