chore: rename package from @hykocx/zen to @zen/core

Update all references across source files, documentation, and
configuration to reflect the new package scope and name. This includes
updating `.npmrc` registry config, install instructions, module
examples, and all import path comments throughout the codebase.

src/modules/modules.actions.js

@@ -5,7 +5,7 @@
  * External modules registered via zen.config.js are resolved through the runtime registry.
  *
  * Usage:
- *   import { getModuleActions } from '@hykocx/zen/modules/actions';
+ *   import { getModuleActions } from '@zen/core/modules/actions';
  *   const { getInvoiceByToken } = getModuleActions('invoice');
  */