What's New now reads like a changelog

The What's New feed listed every release note as one flat bullet list. Because the entries were sorted by title rather than by date, a note from July sat between two from August, and the ten small repairs of a busy day pushed that day's actual new features out of sight.

Entries are now grouped by the day they shipped, newest day first. Inside a day, a new or improved capability gets its own line with its one-line summary, and the day's fixes are bundled into a single "N fixes" line — still linked, still readable in full when you open one, but no longer drowning the rest.

Every note now also carries the label the feed groups by, so a fix looks like a fix and a feature looks like a feature — including the 112 notes written before this change, which were labelled from the pull request that shipped them.