Ambitious attempt for a jam! Oozes aesthetic and the bg music loop is solid. Ran into a few bugs that interrupted the flow but when I didn't hit those the gameloop was solid. Very impressive entry; kind of what I imagine a Dark Reign prototype might've felt like.
Issue wise - on some of my runs I ended up getting drones stuck while gathering crystals and couldn't pull them off to work construction. I built a drone in response and it spawned inside the spike then couldn't leave. Amusing way to soft-lock. I think you suffered a lot from the godot4 build as I've had perf problems with it in previous projects as well. I think v4's html5 export is still a bit lacking.
On the whole well done, I liked what I saw. Cheers!