Hey there (hi, I'm the scripter btw, I just don't talk publicly much cause uhh idk)
And to answer your first question ("how to the devs work as a team"): we all go feral, but at non-overlapping timeframes thus maximizing efficiency and always making some progress in one aspect. But for real, that is sort of what happens unironically. Zumi takes a bunch of work and goes feral at one point, I let tasks pile up and then go feral on them, Jan is feral almost 24/7 except when he sleeps (that's when I'm going feral - maximizing that productivity). The rest go feral for small moments in time almost daily. And to perhaps better answer your question: it's like working on a group project where everyone does the work but the deadline is somewhat more lenient until release day when it's maximum panic cause uhhh bugs really suck fam. And personal thought but everyone in the dev team is like my homie
As for your second question ("what do ppl do to help development"): there are our default tasks. I'm the scripter, Zumi is the artist, Alex and Azery do balance work, Winter does spiriting, etc, etc. Jan works on almost everything else along with overseeing whatever we are doing (perhaps telling Alex/Azery a certain trainer should have a specific set of mons at least, letting me know he needs some different script or some function done, etc, etc). But outside that, tasks also overlap (thank you Alex and Azery for all the AI and battle testing). Obviously, this is my own perspective of things, there may be some other things ppl do which I don't notice cause I almost tunnel vision into scripting at times. Other devs can talk about what they specifically do and other extra stuff that comes on their respective plate.
And happy to see you're enjoying the game so far!