chore: Heimdall 3.0 strategy — backend epic, shared schemas, restructured board

Complete strategy based on 20+ agent research sessions:

Frontend (Track 1): Clean scaffold with Vue 3 + Vuetify 3 + Pinia + ECharts + Vite
Backend (Track 2): Sequelize→Drizzle, class-validator→Zod, auth security fixes
Shared (Track 3): libs/schemas/ with drizzle-zod (blocked by Tracks 1+2)
Packaging (Track 4): saf-packaging mono-repo (independent)

New epics: heimdall2-izw (backend), heimdall2-oma (shared schemas)
Backend subtasks: Drizzle migration, OpenAPI, critical security fixes (P0),
  2FA, refresh tokens, API key improvements

Board: 58 cards (50 open, 8 closed), cross-epic dependencies validated.
Research docs: 07-backend-analysis, 08-migration-paths, 09-heimdall3-strategy

Authored by: Aaron Lippold<lippold@gmail.com>

Author: aaronlippold