Sorry Andrew. I’m just one guy, so the documentation isn’t what you see in an organization. With 02_05_00, I introduced Graph+ and query. I put quite a bit of effort into updating the docs to explain how it all works, and the docs are in the git so readthedocs is version specific.
Beyond that, i’m afraid you would need to look at the diffs to see how I fixed bugs and such.
02_05_04 didn’t have a lot of changes to the firmware, but introduced the latest version of the underlying ESP-IDF/Arduino core. You can find a long list of what’s in that in their git. I don’t know know what half the stuff is and it represents a lot of work over a substantial amount of time by the Espresif folks as well as numerous outside contributors.