Collect end user actions and form session info

## User story

As a person investigating an incident involving end user form submissions,
I want a way to see user actions and session-level data in one place,
So that I can assess what is happening in the user's journey.

## Context

It's difficult to connect/correlate what's happening across systems when the end user is involved:
- How might we log user actions for end user forms within Google Analytics?
- How might we figure out how to query GA for the user journey they followed?

What we currently log:
[GCForms Log Information Types](https://docs.google.com/document/d/1FJn6ZkIg4zEGUXvWsD_id7hBcIUuLlsptn2qCljXsro/edit?tab=t.0)

## Source

This detection issue was proposed as a "Priority 1" action item from the incident [2024-10-25-missing-form-submission](https://docs.google.com/document/d/1KLnuAg5_8xQLGFGqF6uXVDgi3dUUoVmTi4AY-f0rMH0/edit?tab=t.0)