Reorient bb CLI and bb.js API to be centered around being a Noir backend

[johnathan79717]

Problem

The current bb CLI and bb.js API are not optimized for the primary use case of being a Noir backend. The interface should be simplified and focused on making common Noir workflows as easy as possible.

Goals

Build simple demonstration apps

Create dead-simple example applications (any noir circuit will do) that demonstrate:

• Simple JS native verification
• Solidity verification
• Recursive verification

High-level API improvements

Build a high-level API that makes these use-cases as simple as possible:

• Remove as many flags as possible - simplify the interface
• Orient around the simplest use case - e.g., Solidity-friendly should be the default, not require a flag
• Make naming more user-friendly - e.g., --recursion_friendly instead of --use_poseidon2

Separate concerns

• Separate out Aztec-specific functionality from "Noir backend" functionality
• In help text, clearly mark which flags are for 'advanced' use-cases
• Make the default path obvious for typical Noir users

Expected Outcome

bb CLI and bb.js should feel like they were purpose-built as a Noir backend, with Aztec-specific features clearly separated as advanced options.

[AztecBot]

This issue was automatically closed because it was referenced in AztecProtocol/aztec-packages PR #18748 which has been merged to the default branch.

View workflow run

[johnathan79717]

AztecProtocol/aztec-packages#18783 and AztecProtocol/aztec-packages#18899 contributed to this too.

[johnathan79717]

A lot of work has been done. What remains is to decide whether to change defaults and make it a breaking change.