Added README.md files for several @kit packages including Supabase, UI, Emails, Billing, and Mailers. These documents explain the purpose and usage of each package, facilitating better understanding for developers interacting with them.
UI - @kit/ui
This package is responsible for managing the UI components and styles across the app.
This package define two sets of components:
shadn-ui: A set of UI components that can be used across the app using shadn UImakerkit: Components specific to MakerKit