docs: sync final InferEdge status

[hyeokjun32]

Summary

• Synced portfolio docs with the latest validation scope.
• Added latency regression to problem evidence summaries.
• Recorded simplified metric backend and optional pycocotools backend wording.

Validation

• poetry run python3 -m pytest -q

Impact

• Keeps Lab portfolio/status docs aligned with the implemented Local Studio and validation features.
• Avoids stale claims around problem cases and metric backend support.