[bug] New Workspace modal keeps the setup-script prompt after dismissing Configure #5372

Describe the bug

Clicking Configure on the "Setup scripts" sidebar card opens the New Workspace modal pre-filled with a setup-script prompt. If you dismiss the modal without creating a workspace, that prompt stays in the draft. The next time you click + / New Workspace, the composer is still pre-filled with it, even though you never asked to configure setup scripts.

Steps to reproduce

1. Click Configure on the "Setup scripts" card.
2. Dismiss the modal (Esc or click outside) without creating a workspace.
3. Click + / New Workspace.
4. The composer still shows the setup-script prompt. It should be empty.

Cause

The seeded prompt is written to the persisted new-workspace draft and is only cleared on a successful create, so dismissing the modal leaves it behind.

Video