Repair duration display for bad stopped timestamps (#37121)

Workflow run, job, task, and step durations could show **negative**
values (e.g. `-50s`) when `Stopped` was missing, zero (epoch), or
**before** `Started` (clock skew, races, reruns). The UI used
`calculateDuration` with no validation.

This change:

- Uses each row`s **Updated** timestamp as a **fallback end time** when
`Stopped` is invalid but the status is terminal, so duration
approximates elapsed time instead of `0s` or a negative.
- Keeps **`ActionRun.Duration()`** clamped to **≥ 0** when
`PreviousDuration` plus the current segment would still be negative
(legacy bad data).

Fixes #34582.

Co-authored-by: Composer <composer@cursor.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

models/actions/task.go

@@ -77,7 +77,7 @@ func init() {
 }
 
 func (task *ActionTask) Duration() time.Duration {
-	return calculateDuration(task.Started, task.Stopped, task.Status)
+	return calculateDuration(task.Started, task.Stopped, task.Status, task.Updated)
 }
 
 func (task *ActionTask) IsStopped() bool {