Update `getMembershipWitness` interface to have a function for each `tree_id`

[critesjosh]

Create new functions for getting the membership witness for each tree_id,

https://github.com/AztecProtocol/aztec-nr/blob/a3aa6bd5d8f2ad9d44e3d9340550203fbe38c4d6/aztec/src/oracle/get_membership_witness.nr

Current flow includes something along the lines of

context.get_membership_witness(root, tree_id, leaf)

What would be perferred is for the user to not think about the tree_id, as this is a leaky abstraction

context.get_note_hash_membership_witness(root, leaf);
context.get_nullifier_membership_witness(root, leaf)
context.get_contracts_membership_witness(root, leaf)
context.get_archive_membership_witness(root, leaf)