- Remove all FK constraints from models (users, teams, channels, agents)
- Keep fields as optional nullable String for testing DAARWIZZ
- Update SQL migration to remove all REFERENCES
- Fix metadata -> meta in migration
- Allows service to work without base tables for testing
- Remove FK constraint from UserFact.team_id (teams table may not exist)
- Update SQL migration to remove FK constraint
- team_id remains optional String field without FK
- Rename metadata to meta in all models (UserFact, DialogSummary, AgentMemoryFactsVector)
- Update schemas to use meta instead of metadata
- Update SQL migration to use meta column name
- Fixes SQLAlchemy reserved name conflict
