To migrate your Planetcale database to Supabase, follow these steps:

Deploy the latest version of your "yours-sincerely" project with the Supabase URL.
Run the command "npm run generate" to create client.
Run the command "npm run convert" to convert the following models: "User," "Account," "Block," "EnrolledEvent," "Prompt," and "Token".
Finally, execute "npm run post_convert" to convert the models "flag," "post," and "like".

Feel free to reach out if you need further assistance or clarification.