[tooling] anvil version not pinned — fork behavior drifts across foundry releases

[obchain]

Refs #52

Files: scripts/anvil_fork.sh, foundry.toml

Problem

Script calls anvil on $PATH. Foundry release cadence weekly, sometimes breaking (fork protocol changes, EVM semantics changes). Without version pin, PR behavior cannot be reproduced on a clone 6 months later.

Fix

Pin foundry version via foundryup or explicit version check in script:

REQUIRED_FOUNDRY_VERSION="0.2.0-stable"
actual=$(forge --version | head -n1)
[[ "$actual" == *"$REQUIRED_FOUNDRY_VERSION"* ]] || { echo "Foundry version mismatch: expected $REQUIRED_FOUNDRY_VERSION, got $actual"; exit 1; }

Document in README: 'Tested against foundry X.Y.Z — run foundryup -v X.Y.Z to match'.

[obchain]

Fixed on feat/24-anvil-fork (4438673): scripts/anvil_fork.sh now runs anvil --version after the command -v anvil check and compares its first line against ${CHARON_REQUIRED_FOUNDRY_VERSION:-stable}. Mismatch warns loudly with remediation (foundryup -i <ver>) and sleeps 2s before continuing; empty / unreadable output is a hard 127 exit. CHARON_SKIP_FOUNDRY_VERSION_CHECK=1 bypasses the check for CI images. Header documents both knobs.