fix(logs): let a recorded duration outlive a later cancellation

A paused run measures its own active duration at the pause checkpoint.
The previous commit then had cancellation overwrite that with wall clock
from the start, which quietly redefines the column for those runs to
include the time the run spent waiting rather than working — filling a
gap by discarding an answer someone else had already computed.

The duration now coalesces onto whatever the row already carries, so a
cancellation only supplies the value when nothing else did. Every other
cancellation path leaves the column null, so the change is inert there.

Author: waleedlatif1

apps/sim/lib/logs/execution/duration.test.ts

@@ -62,4 +62,17 @@ describe('elapsedDurationMsSql', () => {
     expect(sql).toContain('LEAST(')
     expect(params).toContain(2_147_483_647)
   })
+
+  /**
+   * A paused run records its *active* duration at the pause checkpoint. Elapsed
+   * wall clock through a later cancel includes the time it sat waiting, so
+   * overwriting would silently redefine what the column means for that run.
+   */
+  it('keeps a duration the row already carries', () => {
+    const { sql } = render(new Date('2026-08-13T12:00:05.000Z'))
+
+    expect(sql).toContain('COALESCE(')
+    expect(sql.indexOf('COALESCE(')).toBeLessThan(sql.indexOf('LEAST('))
+    expect(sql).toContain('"total_duration_ms"')
+  })
 })

apps/sim/lib/logs/execution/duration.ts

@@ -28,9 +28,16 @@ import { type SQL, sql } from 'drizzle-orm'
  * fails its transaction and takes the whole cancellation with it. A saturated
  * duration is wrong in the last digit; a failed terminal write is wrong about
  * whether the run ended.
+ *
+ * A duration already on the row wins. This fills a gap; it does not restate an
+ * answer someone else computed. The case that makes the difference is a paused
+ * run: it records its *active* duration at the pause checkpoint, and elapsed
+ * wall clock through a later cancel would silently redefine that to include the
+ * time it sat waiting. On the paths where the column is still null — every
+ * other cancellation — the coalesce is inert.
  */
 const INT4_MAX_MS = 2_147_483_647
 
 export function elapsedDurationMsSql(endedAt: Date): SQL<number> {
-  return sql<number>`LEAST(${INT4_MAX_MS}, GREATEST(1, ROUND(EXTRACT(EPOCH FROM (${endedAt.toISOString()}::timestamp - ${workflowExecutionLogs.startedAt})) * 1000)))::integer`
+  return sql<number>`COALESCE(${workflowExecutionLogs.totalDurationMs}, LEAST(${INT4_MAX_MS}, GREATEST(1, ROUND(EXTRACT(EPOCH FROM (${endedAt.toISOString()}::timestamp - ${workflowExecutionLogs.startedAt})) * 1000)))::integer)`
 }