DSL: Merge aggregation of Honk and AVM RecursionConstraints

[jeanmon]

As part of the DSL integration of the avm recursive verifier, the aggregation object pertaining to the AVM recursion constraint is separate from the one handling the Honk recursion constraints.

See acir_format::process_honk_recursion_constraints() and acir_format::process_avm_recursion_constraints() which both initialized an aggregation object.

Ultimately, it would be more efficient for the public kernel/rollup to aggregate them together.