Use the starter design endpoint and remove the static list of designs

[ramonjd]

We keep a static lists of designs we offer in Gutenboarding over at https://github.com/Automattic/wp-calypso/blob/trunk/packages/design-picker/src/available-designs-config.json

D49406-code introduced a simple endpoint through which we can fetch the sites.

We need a centralized location for these designs so we can manage them more easily as we offer designs over our various platforms/apps, e.g., mobile.

The endpoint: https://public-api.wordpress.com/rest/v1/nux/starter-designs/?language=de

[github-actions]

This issue is stale because it has been 180 days with no activity. You can keep the issue open by adding a comment. If you do, please provide additional context and explain why you’d like it to remain open. You can also close the issue yourself — if you do, please add a brief explanation and apply one of relevant issue close labels.

[ramonjd]

I think this issue is still valid, though a tad stale.

Some thinking might be required in relation to merging the fonts and other metadata currently stored in the static json with the incoming response.

Happy for others to close this issue though. I'd consider it low prio.