fix(cli): support global Composer installs for bin/moko

Check $GLOBALS['_composer_autoload_path'] before falling back to
project-local vendor/autoload.php, allowing the CLI to work when
installed via composer global require.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

bin/moko

@@ -68,6 +68,11 @@ declare(strict_types=1);
 $repoRoot   = dirname(__DIR__);
 $autoloader = $repoRoot . '/vendor/autoload.php';
 
+// Support global Composer installs (e.g. composer global require)
+if (isset($GLOBALS['_composer_autoload_path'])) {
+    $autoloader = $GLOBALS['_composer_autoload_path'];
+}
+
 if (!is_file($autoloader)) {
     fwrite(STDERR, "Error: vendor/autoload.php not found.\nRun: composer install\n");
     exit(2);