Added MAC Core admin application

Property	Value
description	Added the top-level MAC Core admin menu and the shipped plugin management views.
version	1.0.0
type	Create
related	Admin

• Added the top-level MAC Core admin menu in WordPress.
• Shipped the plugin admin surface around the Settings, Helpers, License, and Support views.
• Added the plugin-listing screen links used to reach the management pages and support resources from the installed-plugins table.
• Kept the admin application focused on plugin management, builder-facing helper controls, licensing, and support instead of mixing in project-specific site configuration.