Exit from student essay returns to that student's list

# Exit from student essay returns to that student's list

When a teacher hits "exit" while viewing a student's essay, the navigation should return to that student's essay list — not the class dashboard.

## Problem

Reported 2026-01-15: today, exiting a student essay throws the teacher back to the class dashboard. That's the wrong default — when a teacher is reviewing one student's work, they're usually in a sub-flow ("look at all of Ryan's recent submissions"). Bouncing them up to the class level interrupts that flow and forces extra clicks to dive back in.

## Goals (rough)

- "Exit" navigates one level up (student essay list), not two levels up (class dashboard).
- The breadcrumb / nav header should reflect this.

## Non-goals

- Reworking the entire navigation hierarchy. Targeted fix.

## Open questions

- [ ] What if the teacher arrived at the essay from the class dashboard directly (skipping the student list)? Should "exit" still go to the student list, or back to where they came from?

## Engineering handoff

Not ready. Idea-stage. Small change once decided.