* Move text-input to checkout package
* Add support to TextInput for inputs with type number
* Add ExperimentalDiscountsMeta.Slot to Cart sidebar
* Add extra styles for Button and Panel components
* Add updateCartFromApi util to @woocommerce/blocks-checkout
* Change updateCartFromApi to TypeScript
* Stop passing contexts through the discounts slot fill
* Add CartExtensionsSchema class
* Add CartExtensions Route
* Add register_update_callback and get_update_callback fns
* Add extensionCartUpdate function
* Add applyExtensionCartUpdate action
* Make extensionCartUpdate use batching
* Add ExtensionCartUpdateArgs type definition
* Execute a success/error function after request in extensionCartUpdate
* Remove success and error functions
* Avoid including all schemas in CartExtensionsSchema instantiation
This is achieved by inheriting AbstractSchema and slightly modifying the way in which the latest cart data is returned from this endpoint.
* Update docs for extensionCartUpdate
* Handle errors from extension callbacks
* Throw better errors when incorrect namespace/functions are used
* Add tests for CartExtensions route, ExtendRestApi update callback registration
* Add dummy get_properties method to CartExtensionsSchema