feat(14-03): cache settings/status API and security tests
- api/cloud/cache.py: GET /analysis/cache, PATCH /analysis/cache/settings
- api/cloud/analysis.py: analysis router aggregator (Phase 14 parent)
- schemas.py: CacheStatusOut, CacheSettingsUpdateRequest (explicit allowlists)
- __init__.py: register analysis_router under /api/cloud
- 7 new security tests: admin block, unauthenticated block, object_key exclusion,
response structure, enum validation, tier cap enforcement (T-14-01..02, T-14-08)
- All 47 plan target tests pass (test_cloud_cache.py + test_cloud_security.py)