Missing Alerts for Event Forms

When creating or editing an Event, a function for showing toast messages is missing. When user creates or updates an event, a toast message should be provided for successful creation or updation of an event, or if any error occurs, relevant message should be visible. To display such messages, libraries like React Hot Toast and React Toastify can be used. Even this project uses ShadCN UI, hence Toast component from ShadCN can be used too.

Thank you!