PostureSnapshot model, Alembic migration (b039exec), schemas, service
aggregating all phases (coverage/risk/operations/knowledge/MTTD), and
router at /api/v1/dashboard with executive view, KPIs, coverage-by-tactic,
posture-history, posture-snapshot, and activity-feed endpoints.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
