Improved CORS error handling and authentication fixes

This release improves the developer experience when encountering CORS errors and fixes an authentication issue that previously cleared custom hash parameters during login.

When a CORS error occurs, the SDK now presents a direct link to your project's CORS settings in Sanity Manage.

• Authentication: Fixed an issue where the authentication flow cleared all hash parameters from the URL. Custom hash parameters are now preserved during login.
• TypeScript: Changed ValidProjection to a string type for improved developer experience.
• Error messaging: Improved styling for error messages.
• Dependencies: Updated @sanity/client to version 7.12.0.