Fix 1.6.0 Plugin Check blockers

[mehul0810]

Summary

• Update WordPress.org readme metadata for 1.6.0/current WordPress compatibility and plugin-name policy.
• Remove direct five-star review linking and add direct-access guards to release PHP files.
• Resolve Plugin Check findings for request sanitization, generated admin markup output, Assets Manager checked/selected output, SSL URL parsing, page-cache filesystem checks, script footer loading, debug logging, and translation loading.
• Preserve existing settings, options, and storage contracts.

Validation

• composer validate --strict
• composer lint
• composer test
• composer phpstan
• composer lint-blueprint
• targeted PHPCS on patched release-surface PHP files
• npm run lint
• npm run build
• npm run plugin-zip
• npx playwright test --list
• production-surface Plugin Check: No errors found
• ZIP artifact exclusion/readme metadata inspection
• composer audit --no-dev
• npm audit --omit=dev
• Studio WP plugin status/version smoke
• Feed smoke: 200 RSS response

[github-actions]

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