Add zk-basics exercises for understanding DLP, Schnorr, Pedersen, and other protocols

[surfer05]

I have created a separate zk-basics section for the exercises, which will help people in understanding the basic stuff like Discrete Log Problem, Schnorr Protocol, Pedersen commitment, etc.

[rutefig]

@surfer05 maybe if the section is called zk-protocols-basics gives more context, what do you think?

[surfer05]

yeah, sure, I'll change it to zk-protocol-basics