[tezos] - Make tezos subscriber more generic

[RomarQ]

• Use type annotations to identify the values and their respective field names;
• Validate big_map identifier when accessing the big_map_diff;
• Support custom contract storage as long as mandatory annotations exist in the storage type (%requests, %id, %jobId, %parameters)

This MR makes the Tezos listener less restrict, allowing custom contract storage by parsing the field names from the type specification.