feat: support JSON input files for bb verify command (v2)

[johnathan79717]

Summary

• Re-land of feat: support JSON input files for bb verify command #19800 with fixes for WASM build and bootstrap.sh field names
• Add type-specific JSON structs (VkJson, ProofJson, PublicInputsJson) with named fields per review feedback
• Auto-detect JSON vs binary format in verify command
• Update bootstrap.sh to use new field names (.vk, .proof, .public_inputs, .hash)
• Suppress nlohmann/json sign-conversion warnings for WASM builds using pragma

Size Impact

Build	Without nlohmann/json	With nlohmann/json	Difference
Native bb	63.18 MB	63.20 MB	+19 KB (0.03%)
WASM bb	13.49 MB	13.52 MB	+30 KB (0.22%)

Test plan

• Native build passes
• WASM build passes (with --target bb)
• regenerate_recursive_inputs passes
• JSON prove and verify works end-to-end

[johnathan79717]

Size impact of adding nlohmann/json parsing support to native bb binary:

Version	Size
Without nlohmann/json	63,179,912 bytes (60.25 MB)
With nlohmann/json	63,199,560 bytes (60.27 MB)
Difference	+19,648 bytes (+19 KB, 0.03%)

Negligible impact.

[ludamad]

lgtm but what is the added size to the WASM?

[johnathan79717]

Updated with WASM size impact:

Build	Without nlohmann/json	With nlohmann/json	Difference
Native bb	63.18 MB	63.20 MB	+19 KB (0.03%)
WASM bb	13.49 MB	13.52 MB	+30 KB (0.22%)

Both are negligible.

[AztecBot]

Flakey Tests

🤖 says: This CI run detected 1 tests that failed, but were tolerated due to a .test_patterns.yml entry.

\033FLAKED\033 (8;;http://ci.aztec-labs.com/97ee1f16dfc239b2�97ee1f16dfc239b28;;�): yarn-project/scripts/run_test.sh p2p/src/client/test/tx_proposal_collector/p2p_client.proposal_tx_collector_bench.test.ts (95s) (code: 1) group:e2e-p2p-epoch-flakes (\033Jonathan Hao\033: feat: support JSON input files for bb verify command (v2) (#19966))