What's New now covers every repository

Until now a release note could only be filed from the platform repository. Work that shipped from anywhere else — plugins, courses, content — had nowhere to put an entry, so those changes simply did not appear here. The feed looked complete while quietly under-reporting, and the gap widened every time more of the product moved out of the platform.

Entries can now be written in whichever repository the change was made, and they all arrive in this one feed. What you read here should now reflect the whole product rather than one part of it.