Context

Closes #5063. Helps to continue #4933.

Some of the singular queries are there to select a small sub-object (like FindXxxMetadata queries). A solution is needed for the iterable queries to do the same.

Solution

A projection system, which allows one to query a sub-object (or multiple sub-objects) of the query. This is done by sending a query selector along with the predicate.

Changes

• Predicates are now split into atomic predicates and projections
• The projections are shared with the selectors. The accept a Marker type parameter to determine which kind of object they should store inside
• more macros (than in older predicates impl), should be easier to modify the data model. The predicates, prototypes and projections are now all in one place too.
• Ast predicates are removed, prototype helper methods now return CompoundPredicates directly
• CompoundPredicate's generic now accepts the predicated type and not the predicate type itself
• Some prototype fields were renamed to be in line with the names in the data model

Migration Guide

• Other than some odd renames, regular rust SDK code should not be affected
• The SDKs will require updates for the refactored predicates

Review notes

As with #4833, I tried documenting the system as a whole in iroha_data_model::query::dsl module documentation, so this might be a good place to start to understand the system.

An example use of the API can be found in the smart_contract_can_filter_queries integration test.

Each of the commit represents a logical step towards implementing the new query system. I ensured the tests would pass between those. This might make it easier to review the commits separately than in one big clump.

Checklist

• I've read CONTRIBUTING.md.
• I've written unit tests for the code changes.
• All review comments have been resolved.
• All CI checks pass.
• Fix pytests