PSR-4 split left GatewayInterface/Gateway duplicated across files;
loading BalanceGateway redeclared the interface. Strip sibling types
from polluted files (payment + widgets) so each path owns one type.
Move 288 types from global AKSRT_* + inc/classes manual requires into
namespace AKSRT\{Domain} under src/AKSRT/, wire composer.json psr-4,
and slim bootstrap to helpers/modules/hooks only. Split multi-class
widget/gateway files, update admin contract audit paths, and document
the layout in ADR/README.
kate522