feat: dynamic arrays for experimental-ssa

[guipublic]

Description

Problem*

Test case array-dynamic is now passing

Resolves #1964

Summary*

The PR is now ready for review:

• ACVM and backend relevant PRs have been merged:
  feat: add support for atomic memory opcodes acvm-backend-barretenberg#232
  feat!: atomic memory opcodes acvm#447
• The PR does not handle nested arrays but they are not yet supported.
• Note that the PR does not handle non-homogenous array either.

For non-const index on array operation, we generate a new ACIR opcode corresponding to the operation. This allows ACVM solver to perform stepwise/in-order solving. The backend can easily create the block constraints from them.
Because an array-set generates a new ssa array, we need to copy the array into a new one also in acir-gen. This could be optimised out in case the array we copy is not re-used afterwards. This new array has no more values associated to it so it is mapped to a new AcirArray type.

Documentation

• This PR requires documentation updates when merged.

  • I will submit a noir-lang/docs PR.
  • I will request for and support Dev Rel's help in documenting this PR.

Additional Context

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[Savio-Sou]

@kevaundray / @guipublic seems that this is a bug fix? What needs to be documented exactly?

[guipublic]

@kevaundray / @guipublic seems that this is a bug fix? What needs to be documented exactly?

I don't think it is needed to be documented, as it is adding the dynamic arrays feature to the experimental-sea. It should be transparent for the user.