Update module name and all imports from habit-tracker-api to apocapoc-api.
This reflects the project's new branding as part of the apocapoc ecosystem
(apocapoc-api, apocapoc-web, apocapoc-android).
- Add SQLite and UUID dependencies (go-sqlite3, google/uuid)
- Create database connection with automatic migrations
- Implement UserRepository with full CRUD operations
- Implement HabitRepository with JSON serialization for arrays
- Implement HabitEntryRepository with date range queries
- Add comprehensive test coverage for all repositories
- Fix User entity to default timezone to UTC when empty
- All tests passing with TDD approach (Red-Green-Refactor)