Added a new feature to the subscription block which displays newsletter categories. The added categories are styled and displayed above the subscription form. Also added a new hook to query newsletter categories from the backend. This feature enhances user experience by offering categorized subscribing options. The form width is reduced when categories are displayed for better aesthetics.

Added a new feature to the subscription block which displays newsletter categories. The added categories are styled and displayed above the subscription form. Also added a new hook to query newsletter categories from the backend. This feature enhances user experience by offering categorized subscribing options. The form width is reduced when categories are displayed for better aesthetics.

The changes introduced a new 'enabled' state to the useNewsletterCategories hook. This was done to allow better manipulation of the subscription blocks based on whether the newsletter category function is enabled by the user or not, hence improving user experience when interacting with subscription blocks.

This commit removes the additional two lines of spacing at the beginning of the view.scss file within the subscriptions block. This was done to clean the code and make it adhering to the standard coding practices, which enhances the readability and maintainability.

… client-side fetch

This commit introduces a new REST API endpoint for retrieving the newsletter categories. The new endpoint will enable a more seamless and effective integration of these categories in the client-side.

Moreover, modifications were also made to the 'trait-wpcom-rest-api-proxy-request-trait.php' file. Now the body for Client::wpcom_json_api_request_as_user is checked if not null. This was done to prevent an error when the body is null.

Lastly, the fetch request at 'use-newsletter-categories.js' has been updated to use the new /newsletter-categories endpoint within the local server environment instead of making a direct request to the public API.

In the subscriptions module, a mock function was added in the test/edit.js file. This was done to simulate the behavior of the actual 'useNewsletterCategories' function in the unit tests. This will facilitate the testing process by controlling its response and help in improving the code coverage.

- Renamed --border-radius to --subscribe-block-border-radius
- Removed check of WPCOM

…ck-add-newsletter-categories