chore(2meet-data-optimizer): make the hardening branch pass PHPStan and PHPCS

- CI PHPStan (level 6, baseline for pre-existing debt) failed on 35 errors in
  code added on hardening/2.0: missing iterable value types (PHPDoc only), a
  redundant method_exists() in uninstall.php, and the new WP-CLI commands
  registered as array('Class', 'instanceMethod') — now array(new Class(), ...)
- Local runs had been masked by a PHPStan tmpDir shared with the act CI runner
  (cached container pointing at a removed phar); use a private tmpDir
- Verify: phpstan (private tmpDir) no errors, phpcs clean on changed files,
  phpunit Unit 658 OK; dev22 (running this branch) CLI post-status-sync /
  bridge-restore-native dry runs OK

uninstall.php

@@ -77,7 +77,7 @@ $wpdo_for_each_site = static function ( callable $callback ) use ( $wpdo_site_id
 };
 
 // ── Refuse while any site holds data that exists only in wpdo_* tables ───
-if ( ! $bootstrap_ok || ! method_exists( 'TMDO_Installer', 'uninstall_blockers' ) ) {
+if ( ! $bootstrap_ok ) {
 	wp_die( esc_html( '2meet Data Optimizer：無法載入資料安全檢查，為避免資料遺失，已停止解除安裝。' ) );
 }