Turf Stats 1.17.0

This release prepares Turf for submission to the WordPress.org plugin directory. No changes to tracking behavior or reports.

• Plugin renamed to "Turf Stats" — WordPress.org requires at least 5 latin letters in the plugin name (it generates the initial slug from it); "Turf" alone doesn't qualify. The GitHub repo, text domain, and internal function names (turf_*) are unchanged.
• readme.txt added in the WordPress.org format, including an FAQ section covering exactly what data is collected, where it's stored, and how long it's kept.
• uninstall.php added: by default, only the plugin's own bookkeeping (db-version options, the scheduled pruning event) is removed when you delete the plugin — your collected statistics are kept, so an accidental delete/reinstall doesn't wipe years of history. Opt in to full data removal with define( 'TURF_REMOVE_DATA_ON_UNINSTALL', true ); in wp-config.php before deleting.
• Direct-access guards added to every PHP file (some files previously only referenced ABSPATH inside a file path, which isn't a guard).
• The GitHub-based update checker is now conditional and is stripped entirely from the build submitted to WordPress.org — wp.org-hosted plugins must receive updates from wordpress.org itself, not a third-party server. This GitHub release and its update mechanism are unaffected; existing installations continue to update from here exactly as before.
• Various escaping, translator-comment, and SQL-preparation cleanups flagged by the WordPress Plugin Check tool (the same tool the wp.org review team uses) — down to zero reported errors.