ed_on_bn254 isn't compatible with ERC-2494 babyjub

[TheFrozenFire]

I've been porting my circom/snarkjs circuits to arkworks, and found that the implementation of ed_on_bn254 isn't compatible with the curve as described in ERC-2494, in the iden3 js-crypto library, and in the circomlib circuits.

Particularly, the TECurveConfig specifies an a coefficient of 1, calculates the d coefficient in some manner I'm not familiar with, and specifies an affine generator which is different from the spec. The MontCurveConfig is similarly different in specifying the b coefficient as 1.

By "fixing" the coefficients, and using the base 8 point, I get the same outputs as js-crypto and circomlib produce.

Is there some logic underlying the difference in arkworks' implementation of babyjub?