Uncomment the ruff check and pytest steps in the Gitea Actions build
workflow so that linting violations and test failures block image builds.
Fix all pre-existing ruff violations (E402 import ordering in analyzer.py,
F821 undefined name in api.py, I001 unsorted imports in test files, F401
unused import in test_rate_limit.py).
Closesleeworks-agents/SPARC#1559Closesleeworks-agents/SPARC#1560
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>