temp: add phpcheck.php to diagnose PDO availability

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

phpcheck.php

@@ -0,0 +1,7 @@
+<?php
+echo "PHP versio: " . PHP_VERSION . "\n";
+echo "PDO loaded: " . (extension_loaded('pdo') ? 'KYLLÄ' : 'EI') . "\n";
+echo "PDO MySQL: " . (extension_loaded('pdo_mysql') ? 'KYLLÄ' : 'EI') . "\n";
+echo "MySQLi: " . (extension_loaded('mysqli') ? 'KYLLÄ' : 'EI') . "\n";
+echo "\nLadatut laajennukset:\n";
+echo implode(', ', get_loaded_extensions());