Snapping looks good. How do you export it and use it in a game?

Well, HC (depending on the version) works. Latest update was a year ago. I have tested it and it worked OK, but went with love.physics module after all.

Also maybe https://love2d.org/wiki/love.graphics.setScissor might be of help to contain drawing operations.

windfield is outdated and abandoned (therefore you will be lucky if anybody investigates). I would recommend against using it. Try breezefield that receives updates:
https://github.com/HDictus/breezefield

Alternatively you can use native love.physics module.

Looks good. Are more screenshots available? I think that would help Github users.

Nice and well documented!

Can you provide the relevant code, e.g. where the deletion happens? Probably you are creating enemy instances as a reference, not a copy.

Not sure what central management is? Globals? Functional programming does not mean central management and global variables.

You need to follow the docs and function signatures and not include random copied/pasted params:
love.graphics.translate( dx, dy )
https://love2d.org/wiki/love.graphics.translate

Congrats! Can you provide some up-to-date tips on Steam integration? Honestly I didn't really do any. I might add achievements at some point though. As far as publishing / deploying it - The technical side of it was kind of hard for me to grasp at first. The steamworks backend is not terrible, but ...