- Fix S110: replace bare except-pass with explicit degrade behavior
- Fix E501: wrap long function signatures to <=120 chars
- Fix I001: sort imports in test file (resources to top)
- Fix PT018: split composite assertions into separate statements
- Add _BoomInstance for provider-error testing
- Add 5 degrade tests (analyze_goal, propose_plan_v1 x2, discover_resources, learn_from_build)
- Remove unused _KIND_BY_PREFIX dict
- Add noqa comments for test mock arguments
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>