Setting error.handled is True when querying for errors in Discover returns Internal Error

### Environment

SaaS (https://sentry.io/)

### Steps to Reproduce

Set error.handeld is True inside discover or when making an alert. It works when is:unresolved is unchecked.

### Expected Result

The filter works and I can see the list of errors where error.handled is True.

### Actual Result

Internal Error. Your query failed to run.

### Product Area

Issues

### Link

https://sentry.sentry.io/issues/6656786701/?project=1&query=is%3Aunresolved%20user.email%3A%EF%80%8DContains%EF%80%8Dcolin.kawai%40sentry.io&referrer=issue-stream

### DSN

_No response_

### Version

_No response_

Start by reproducing the Discover query with error.handled set to True while is:unresolved is enabled, and compare it with the working query where that filter is unchecked. Trace the failing query path and verify that the filter returns the matching errors without an Internal Error.

Written by the indexing model from the issue text.