Typeorm

- [x] setup typeorm
- [x] setup database entities/models
- [ ] migrate queries to use sqlite db through typeorm

The issue involves migrating existing queries to use SQLite via TypeORM. First, examine the current query logic in the codebase to understand the data access patterns. Then, review the already-setup TypeORM entities and configuration. The goal is to replace direct database calls with TypeORM repository or query builder methods, ensuring the GraphQL API layer continues to function correctly.

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