Allow transforms in schemaTasks

I might be missing something here, but I tried defining the schema in a schemaTask using a Zod object with .transform(), and I wasn’t able to get it to work. My guess is that Trigger might actually parse the Zod object twice, breaking the transform.

I wound up just using a regular task with an unknown payload type and then parsing the payload within the task itself, but it’d be nice to either support transforms or add documentation indicating that they aren’t supported.