Reparses a point as secp256k1, for entry points that take the structural point type.
Parameters
point: WeierstrassPoint<bigint>
Returns WeierstrassPoint<bigint>
Remarks
WeierstrassPoint<bigint> is shared with the other curves and scalar multiplication does not
check membership, so a point that never went through a secp parser has to be sent through one.
Reparses a point as secp256k1, for entry points that take the structural point type.