This was incredibly hard to judge. Thank you everyone who took time to contribute around the Bevy community during Bevy Jam!
And the winner is...
https://itch.io/profile/shadowcurse
https://github.com/shadowcurse
https://festus.itch.io/absconder
ShadowCurse submitted this PR to improve the "heron" crate, which is a Bevy plugin offering an ergonomic layer on top of "bevy_rapier" for physics. While it wasn't merged, I though this was a nice example of collaboration in the wider Bevy community. They also got bonus points for mentioning the Bevy Jam.
https://github.com/jcornaz/heron/pull/219
Honorable mentions (in no particular order)
Djee (Super Kaizen Overloaded) While not actually a PR, this jammer took time during the jam to document an issue an a workaround in a third party bevy crate. This ultimately spurred an interesting discussion about abandoned crates and a potential "Bevy Community" organization to adopt them.
https://github.com/JonahPlusPlus/bevy_atmosphere/issues/6
Cart (Build A Better Buddy) really doesn't like typing! Considering how my game placed in the jam, it seems that a lot of you agree!
https://github.com/bevyengine/bevy/pull/4071
XBagon (Ad Opt) loves PRs so they PRed a PR.
https://github.com/jakobhellermann/bevy/pull/26
mdenchev (Bevy Cursed Tomb) is trying to fix bleeding in atlases.
https://github.com/bevyengine/bevy/pull/4163
jamescarterbell (Bevy Cursed Tomb) is trying to improve the ergonomics of working with Commands from parallel iterators.
https://github.com/bevyengine/bevy/pull/4068
Vleue (Cleanse) is trying to improve ergonomics around scenes loaded from gltf files.