Chore: clean up undefined names in playground

[nonprofittechy]

[BryceStevenWilley]

From my experience, these fall under a few different issues with the undefined playground names feature:

• actual errors; rename_pdf_fields isn't referenced correctly from what I can tell
• it doesn't detect try-catch exception variables and with context's as variable names, so those are considered undefined. I think those need an upstream update
• variables defined in events aren't considered defined, since they can't directly by triggered. Not sure how to address this one
• variables under only sets (which I think we needed when integrating I'm feeling lucky, right?) act the same as events

[nonprofittechy]

Agreed. My approach has been to look through them one by one, fix the ones that are actual errors, and then add a dummy objects block that defines the rest to DAEmpty. It would be nice to fix upstream but until then, clearing the errors that don't actually show an error state is something I prefer--that way we can use the information to catch actual errors, like the one out of 13 you found here!