feat: surface AgentKit build logs in Studio deployments

[FirstayZheng]

Summary

• stream Code Pipeline build logs during AgentKit deployment and attach them to deployment SSE updates
• show build logs inline beside the build-image step with accumulation, auto-scroll, collapse behavior, and clearer failure messaging
• document local ruff/pyright installation notes for Studio development

Tests

• uv run pre-commit run --all-files
• npm test
• npm run build
• uv run pytest tests/cli/test_frontend_deploy_errors.py -q

Note: npm run build reports existing Vite chunk/dynamic-import warnings.