Update FAQ guidance after Google rich result removal

[sashatexb]

Summary

• update FAQ guidance after Google removed FAQ rich results for every site on May 7, 2026
• distinguish valid Schema.org FAQPage markup from Google rich-result eligibility
• remove the government/healthcare validator restriction and unsupported AI-visibility claims
• align schema, page, planning, SXO, Search Console, PDF, and agent guidance
• add regression coverage for analyzer, hook, and skill instructions

Root cause

The existing suite reflected Google's August 2023 restriction to government and healthcare sites. Google deprecated the FAQ feature on May 7, 2026 and removed its documentation in June 2026, so site-type eligibility and related AI-visibility recommendations were no longer current.

Official source: https://developers.google.com/search/updates#june-2026

Validation

• python -m pytest tests/ — 59 passed
• targeted FAQ guidance tests — 3 passed
• shell syntax checks passed
• changed Python files compiled successfully
• git diff --check passed