Task page waiting-row action bar polish

Seen on the task page (local stack, desktop 1280 and phone 400) while verifying Task 8096, on a row waiting on a question (`awaiting_response`), Task tab: 1. The bar's reason line ("Waiting on a question. Answer it, or save and restart.") names the Answer tab but does not link to it; make "Answer it" select the Answer tab. 2. On an unchanged waiting row the bar shows two dead buttons side by side (Save greyed for no changes, Go greyed for the question); on a phone they take the full bar. Consider hiding Go while the row cannot start, and keeping only the reason line. 3. At phone width "Assigned to" is stowed in Advanced even though it now reads "Unassigned"; consider showing an unset assignee on the main form so the gap is visible. Out of scope: Go's start/reset semantics, the Task 8084/8096 hold and late-reset behaviour. Done means: - Each item fixed or ruled out with a one-line reason; vitest covers what changed; a live screenshot at desktop and phone width.

Task page waiting-row bar: "Answer it" opens the Answer tab, Go is removed while the row can't start, and an unset assignee shows on the main form on phones. Quick gate and vitest green; screenshots taken at desktop and phone. PR #6322 queued in the merge lane. Follow-ups filed as draft 8117.