Switch public execution to public dispatch function

[fcarreiro]

The concept of function selector in public will only stay in Aztec-nr and be deshrined from protocol/avm.

• Create macro for public dispatch
• Reroute public execution through public dispatch
• Only register/deploy public dispatch
• Fix stack trace (see this)
• Deshrine function selector from protocol-public
• Correctly constrain call enqueueing from private

[fcarreiro]

Writing this here regarding the unsafe call to enqueue_public_function_call_internal and possible fixes.

IDK who will be doing this since it's not an AVM thing. Maybe us, maybe not.

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Possible solutions:

1. The easy way to make this secure, IIRC, is to constrain the hashes there in place. Something like assert(old_hash == hash([a,b,c])) and assert(new_hash == hash([selector,a,b,c]). This would blow up the constraints and when I was doing this everyone was chipping away constraints so I thought it wouldn't fly.
2. Something that I tried was to change the the private interfaces (macros) and call methods to take a slice. Then I could do the same as I did in public. This didn't work because sizes need to be known at comptime sadly.
3. The other possible solution (more elegant from some PoV and less from other) is to change all the users of the "call with hash" method to include the selector themselves. IIRC from a discussion with Palla, the major offenders and only real need for passing the hash are the contract (?) entry points which then kind of call other functions with an already given set of params. Selectors are now an aztec-nr/js only concept but IIRC then it would be ok to change the JS code to insert the selector appropiately.