test: Groth16 for proving (not for merging, just testing)

[jonesmarvin8]

🎯 Purpose

This branch enables real Groth16 proofs generated using Risc0. Previous tests with Groth16 proofs resulted in errors on certain systems. Two specific errors were identified resulting in failed tests:

• Insufficient memory
• Non x86 architecture

These directions assume that Docker is installed. We provide two sets of directions (Linux setup and non x86).

Path 1: x86 / Linux setup

1. If using Docker Desktop, raise Settings → Resources → Memory to 8 GB+. (Docker Engine on
   Linux typically has no cap by default.)
2. Run with the prove feature enabled, pointing RISC0_WORK_DIR at a persistent directory
   so proving artifacts (seal.r0, input.json) survive the run:

   RISC0_WORK_DIR=/path/to/work-dir cargo test -p lee --release --features prove \
     prove_privacy_preserving_execution_circuit_public_and_private_pre_accounts -- --nocapture

   (Substitute your actual Groth16 entrypoint if different.)
3. (Optional, if step 2 failed with exit 137) Replay the captured artifacts standalone to
   test different memory caps without re-running the full proving step each time:

   docker run --rm --memory=8g \
     -v /path/to/work-dir:/mnt \
     risczero/risc0-groth16-prover:v2025-04-03.1

   (8 GB is the verified floor — 6 GB and below fails with exit 137/OOM.)

Path 2: non-x86 (ARM64 — Apple Silicon, ARM64 Linux)

1. macOS only: if using Docker Desktop, enable Settings → General → "Use Rosetta for
   x86/amd64 emulation on Apple Silicon."
2. Linux only (no Docker Desktop): register emulation once per host:

   docker run --privileged --rm tonistiigi/binfmt --install all

3. If using Docker Desktop, raise Settings → Resources → Memory to 12 GB+. (Higher than x86
   to cover emulation overhead; not empirically verified like the 8 GB x86 figure.)
4. Force the amd64 platform and run, pointing RISC0_WORK_DIR at a persistent directory so
   proving artifacts survive the run:

   RISC0_WORK_DIR=/path/to/work-dir DOCKER_DEFAULT_PLATFORM=linux/amd64 \
     cargo test -p lee --release --features prove \
     prove_privacy_preserving_execution_circuit_public_and_private_pre_accounts -- --nocapture

   (Forcing amd64 is required — the image's native arm64 build is unofficial/unsupported
   upstream and fails with exit 125.)
5. (Optional, if step 4 failed with exit 137) Replay the captured artifacts standalone to
   test different memory caps:

   docker run --rm --platform=linux/amd64 --memory=12g \
     -v /path/to/work-dir:/mnt \
     risczero/risc0-groth16-prover:v2025-04-03.1

Quick troubleshooting reference

Exit code	Likely cause
137	Out of memory — raise --memory
125	Wrong/unsupported platform resolved (ARM64: force linux/amd64), or daemon/image issue

⚙️ Approach

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🧪 How to Test

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🔗 Dependencies

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