fix: handle rng-seed values greater than 2^32-1

[asaites]

Values larger than $2^{32}-1$ should be converted to a byte array before passing them onward to the seeded-random-state function.

Note to reviewers: I am not experienced with lisp, and so used generative AI to write the integer->ub32-vector function. My apologies if it is not a particularly idiomatic way to accomplish this in lisp, but in any case, the important aspect for the fix is that get-random-state converts larger values to an array (or rejects them).

Closes: #327

[stylewarning]

Thanks for the patch. I'll try to have it reviewed by tomorrow.