Feature Request: Detect when survey responses don't match question type

Feature request

Is your feature request related to a problem?

I've seen a few support requests where the format of survey responses didn't match the expected format for the question type. Often this is because the question type has been changed, or possibly because an API survey has been incorrectly implemented.

This has confused users, as it looks like responses are missing.

It would be nice if we could somehow give the user some feedback that we're receiving response, but in the wrong format for the question.

Additional context

From: https://posthoghelp.zendesk.com/agent/tickets/34760 (moved to PostHog: https://us.posthog.com/project/2/support/tickets/36879)

Debug info

Kind: support

Target area: surveys

Report event: http://go/ticketByUUID/0d3ee6a8-4fb2-499b-be91-bce7ca0d1777

Session: https://us.posthog.com/project/sTMFPsFhdP1Ssg/replay/0198365f-d6c7-76b5-9bea-8704ccb93c5c?t=1123

Exceptions: https://us.posthog.com/project/2/error_tracking?filterGroup=%7B%22type%22%3A%22AND%22%2C%22values%22%3A%5B%7B%22type%22%3A%22AND%22%2C%22values%22%3A%5B%7B%22key%22%3A%22%24session_id%22%2C%22value%22%3A%5B%220198365f-d6c7-76b5-9bea-8704ccb93c5c%22%5D%2C%22operator%22%3A%22exact%22%2C%22type%22%3A%22event%22%7D%5D%7D%5D%7D

Location: https://us.posthog.com/project/60501/surveys/01968073-bf3f-0000-67dd-11339a8c394e

Persons-on-events mode for project: person_id_override_properties_joined

No files, tests, or code entry points are named; start by locating the survey response handling and question-type validation described in the issue. Use the linked support context to define how mismatches should be surfaced, then establish tests that distinguish valid responses from responses in the wrong format.