This PR is an attempt to remove transaction candidates so that Anoma transactions no longer need to be preprocessed (i.e. being run through the Nock VM three times over) before being executed. Specifically, the following changes have been made:

• Removed the threefold Nock evaluation of transaction code by nodes so that the transaction bytes are now sent directly to the backend
• Removed the Nock wrapping/bytes placed around transactions during submission since the RPC now expects the transaction itself rather than something that eventually evaluates to the transaction
• Added an RPC function that allows clients to query the blobs at specified keyspaces since this can no longer be done through read only transactions (which require Nock evaluation)
• Modified scry function for proving so that it directly queries the blob at a given keyspace instead of sending a read only transaction (that contains a scry).
• Replaced constants/byte sequences around the codebase with the result that would have been obtained by executing the Nock VM on them. This reflects the fact that nodes no longer do this execution.