This commit includes the following changes:
- Deleted the `package-lock.json` file to streamline dependency management.
- Updated the `financials.py` endpoint to return a comprehensive user financial summary, including net balance, total group spending, debts, and credits.
- Enhanced the `expense.py` CRUD operations to handle enum values and improve error handling during expense deletion.
- Introduced new schemas in `financials.py` for user financial summaries and debt/credit tracking.
- Refactored the costs service to improve group balance summary calculations.
These changes aim to improve the application's financial tracking capabilities and maintain cleaner dependency management.
