Add MaxArtifactFiles and MaxArtifactTotalBytes to SandboxConfig:
- Default MaxArtifactFiles: 10,000 (configurable via SecurityDefaults)
- Default MaxArtifactTotalBytes: 100GB (configurable via SecurityDefaults)
- ApplySecurityDefaults() sets defaults if not specified
Enforce caps in scanArtifacts() during directory walk:
- Returns error immediately when MaxArtifactFiles exceeded
- Returns error immediately when MaxArtifactTotalBytes exceeded
- Prevents resource exhaustion attacks from malicious artifact trees
Update all call sites to pass SandboxConfig for cap enforcement:
- Native bridge libs updated to pass caps argument
- Benchmark tests updated with nil caps (unlimited for benchmarks)
- Unit tests updated with nil caps
Closes: artifact ingestion caps items from security plan
**Payload Performance Test:**
- Add job cleanup after each iteration using DeleteJob()
- Ensure isolated memory measurements between test runs
**All Benchmark Tests:**
- General improvements and maintenance updates
- Surface GPUDetectionInfo from parseGPUCountFromConfig for detection metadata
- Document FETCH_ML_TOTAL_CPU and FETCH_ML_GPU_SLOTS_PER_GPU env vars
- Add debug logging for all env var overrides to stderr
- Track config-layer auto-detection in GPUDetectionInfo.ConfigLayerAutoDetected
- Add --include-all flag to artifact scanner (includeAll parameter)
- Add AMD production mode enforcement (error in non-local mode)
- Add GPU detector unit tests for env overrides and AMD aliasing
- Add logs and debug end-to-end tests
- Add test helper utilities
- Improve test fixtures and templates
- Update API server and config lint commands
- Add multi-user database initialization
