Add customizer support for OpenSCAD

This also includes sending metadata and part of the concatenated gzip,
not in the s3 metadata as that has a 2kb limit.

Resolves #320

app/web/src/components/IdeConsole/IdeConsole.tsx

@@ -22,7 +22,7 @@ const IdeConsole = () => {
               {time?.toLocaleString()}
             </div>
             <div className={(type === 'error' ? 'text-red-400' : '') + ' pl-4'}>
-              {message.split('\n').map((line, index) => {
+              {(message || '').split('\n').map((line, index) => {
                 return (
                   <div key={index}>
                     {line.startsWith('ECHO:') ? (