fix backchannel 4
fix PSR-4 autoload warning: switch to classmap for includes/ WordPress file naming convention (class-foo-bar.php) does not comply with PSR-4 which expects FooBar.php. Use classmap so Composer scans the directory without filename constraints and eliminates the build warning. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>