Clarify zkApp MIP

[L-as]

It is vague on details and misleading at certain points, e.g. phrasing such as "Account A has granted a smart contract access to drain his funds" which isn't how it really works under the hood, creating confusion.

Ideally it should explain what account updates are, what each field does precisely, what the semantics are, what the public input passed in to the circuits actually is (i.e. the hash of the account update and child forest AFAIK), how token owners work, what token slots, are, etc.

E.g. it currently says "if a custom token is involved, the token permissions are checked", how is it checked? By the owner? Sure. Where can it be in the tree? Can the token owner be an account of any token, or only the Mina token?

It leaves much unexplained.