API: consider using APIv3 standard endpoints

[humitos]

Now that we are allowing public access to APIv3 endpoints, we can think about making different API queries using the common APIv3 endpoints to fetch small chunks of data instead doing one big call to the specific /_/addons/ one.

This would be transparent for our own JavaScript library and for users of the CustomEvent because it will be managed internally and the exact same JSON-like object will be returned.

As a example,

• projects.current field can be populated with https://docs.readthedocs.io/en/stable/api/v3.html#project-details
• versions.current field with https://docs.readthedocs.io/en/stable/api/v3.html#version-detail
• versions.active field with https://docs.readthedocs.io/en/stable/api/v3.html#versions-listing

This may be something good to explore since I'm seeing some benefits on caching (not all of the responses will be purged on each new build) and also in maintenance as well, since it's going to be one less big endpoint to maintain over time. Besides, we will become users of our own APIv3 which will make us to keep improving it over time.

• API V3: change permissions to allow anonymous access to public resources readthedocs.org#11485