Feature-gate cairo/foundry + update EVM bb CLI flow

[0xpantera]

Summary

• add compile-time feature gates for cairo and evm-foundry and gate CLI/test/doctor behavior
• update EVM bb CLI integration to verifier target (-t evm) with VK-first prove flow
• change EVM calldata to JSON derived from binary proof + public_inputs
• refresh README for feature flags and bb CLI usage

Notes

• CHANGELOG and other analysis markdown files are intentionally not included in this PR per request.