The application was displaying duplicate toast notifications due to events being triggered multiple times. This commit prevents duplicate notifications.
Addresses issues where budget and expense data were not displaying correctly on the summary cards, category bar graph, and transaction/analytics pages. Also fixes a bug where data was disappearing after input.
Refactors the `useBudgetState.ts` file into smaller, more manageable files to improve code organization and maintainability. No functionality is changed.
