fix: format Local Studio runtime values

[hyeokjun32]

Summary

• Normalized structured Runtime result fields before rendering Studio metrics.
• Prevented model, backend, and device objects from appearing as [object Object].
• Clarified Compare View when the latest imported pair uses the same backend.
• Bumped Studio static asset references to v7.

Validation

• poetry run python3 -m pytest tests/test_studio_routes.py -q
• poetry run python3 -m pytest -q
• Manual HTTP check for /studio v7 assets and updated app.js rendering helpers

Impact

• Makes imported Runtime results readable in the Job / Result panel.
• Reduces confusion when repeatedly importing the same result file.

Notes

• No DB, queue, auth, upload, or production SaaS behavior was added.