Fix CustomApiError

✅ Solution

CustomApiError often arises in Next.js due to multiple instances of the same error class being created across different bundles or environments (server vs. client), causing `instanceof` checks to fail. Ensure your custom error class is defined in a single, shared module and is imported from the same absolute path consistently throughout your application, which will prevent module duplication and restore proper `instanceof` behavior. Consider using a bundler analyzer to identify and eliminate duplicate modules if necessary.