feat: add wave 2 code benchmark adapters

[aabbdev]

Summary

• add the pinned public LiveBench Coding 2024-11-25 task and benchmark-specific extraction/scoring semantics
• add BigCodeBench v0.1.4 complete/instruct and full/hard surfaces with the official amd64 evaluator plus a reproducible source-equivalent arm64 Hard runtime
• keep generated programs behind network-disabled, read-only, capability-dropped Docker sandboxes and fail closed when canonical BigCodeBench calibration cannot run
• add source-backed protocol audits for OJBench, TIR-Bench, Codeforces ELO, Spider, VITA-Bench, and MEGA instead of exposing approximate scores

BigCodeBench arm64 evidence

The canonical Hard preflight improved from 79/148 to 145/148 after resolving the evaluator dependency set and routing writable caches to tmpfs. The remaining records (BigCodeBench/101, /590, and /1012) require live external downloads; they now produce canonical evaluation errors and no model score while networking remains disabled.

The arm64 runtime is therefore restricted to subset="hard". subset="full" requires the official runtime until a separate full-suite validation is completed.

Validation

• pre-commit run --all-files
• pytest — 464 passed, 11 skipped
• targeted BigCodeBench mypy — success across 6 source files
• canonical BigCodeBench Hard arm64 preflight — 145/148, 3 network-dependent fail-closed records
• locked arm64 image rebuild — 143-package lock matches the built image
• arm64 Docker Compose smoke — passed with network disabled/read-only filesystem
• uv build — wheel and sdist built; Dockerfile, both compose files, and arm64 lock verified in artifacts

Known limitations

• the pinned official linux/amd64 BigCodeBench image still needs a privileged native x86_64 Docker smoke; QEMU on Apple Silicon segfaulted and the available GPU instance disallowed layer registration/unshare
• strict parity for the three network-dependent Hard records requires immutable audited fixtures, not enabling network for generated code

[github-actions]

✅ Benchmark documentation has been automatically updated.