* consensus/misc, params: add EIP-4844 blobfee conversions * consensus/misc: pull in fakeExponential test cases * consensus/misc: reuse bigints * consensus/misc: nit renames, additional larger testcase --------- Co-authored-by: Roberto Bayardo <bayardo@alum.mit.edu> Co-authored-by: Martin Holst Swende <martin@swende.se>