[lukan]

"turn the canvas you authored into finished, consistent art"

Like a jpeg? Otherwise I don't understand your question.

" a way to turn natural language rules into correct code"

And this is straight impossible, as natural language is by definition ambigious in meaning and code is not. Try your luck with LLM's, they come closest.

(a subset of natural language might work, but this is kind of a complex research topic)