Fix LiveRunWidget activeRun merge bug and add idle_warning clear test

- Fix: activeRun merge in LiveRunWidget was dropping errorCode and
  lastOutputAt, preventing idle badge and last-output display from
  rendering for active runs
- Add test: verify reportRunActivity clears idle_warning error code
  and updates lastOutputAt

Co-Authored-By: Paperclip <noreply@paperclip.ing>

server/src/__tests__/heartbeat-process-recovery.test.ts

@@ -332,4 +332,22 @@ describeEmbeddedPostgres("heartbeat orphaned process recovery", () => {
     expect(run?.errorCode).toBeNull();
     expect(run?.error).toBeNull();
   });
+
+  it("clears the idle warning when the run reports activity again", async () => {
+    const { runId } = await seedRunFixture({
+      includeIssue: false,
+      runErrorCode: "idle_warning",
+      runError: "Idle warning: no output for 10 minutes",
+    });
+    const heartbeat = heartbeatService(db);
+
+    const updated = await heartbeat.reportRunActivity(runId);
+    expect(updated?.errorCode).toBeNull();
+    expect(updated?.error).toBeNull();
+    expect(updated?.lastOutputAt).toBeTruthy();
+
+    const run = await heartbeat.getRun(runId);
+    expect(run?.errorCode).toBeNull();
+    expect(run?.error).toBeNull();
+  });
 });

ui/src/components/LiveRunWidget.tsx

@@ -68,6 +68,8 @@ export function LiveRunWidget({ issueId, companyId }: LiveRunWidgetProps) {
         agentId: activeRun.agentId,
         agentName: activeRun.agentName,
         adapterType: activeRun.adapterType,
+        errorCode: activeRun.errorCode,
+        lastOutputAt: toIsoString(activeRun.lastOutputAt),
         issueId,
       });
     }