Replace 35 incremental migration files with one comprehensive initial
migration that captures the complete database schema. This simplifies
the migration history and eliminates complex dependency chains between
migrations.
The new migration (6a4c4ed4a5c6) includes all tables for:
- Users, organizations, and authentication
- SSH CA and certificate management
- ZeroTier network integration
- OIDC/OAuth providers
- Security policies and audit logging
