Handle Rollup warnings as errors

Author: colinrotherham

rollup.config.mjs

@@ -36,6 +36,11 @@ export default defineConfig(
           },
         }),
       ],
+
+      // Handle warnings as errors
+      onwarn(warning) {
+        throw new Error(warning.message, { cause: warning });
+      },
     }),
   ),
 );