This commit removes the redundant `use-toast.tsx` file and refactors the authentication methods in `personal-accounts-server-actions.ts` to enhance service integration and data handling. UI components like `LanguageDropdownSwitcher` and `site-header-account-section.tsx` have been refined for better readability. Changes in the `config.tsx` file aim to improve the overall code cleanliness. The `schema.sql` file under migrations was updated to cascade delete for 'invited_by' reference.
