fix: pipeline editor UX improvements

src/app/(dashboard)/fleet/page.tsx

@@ -108,7 +108,7 @@
     environmentsQuery.isLoading ||
     nodesQuery.isLoading;
 
   const rawNodes = nodesQuery.data ?? [];
 
   // Sort client-side
   const nodes = useMemo(() => {
@@ -186,15 +186,15 @@
   return (
     <div className="space-y-6">
       <div className="flex items-center gap-1">
+        <span className="rounded-full px-3 h-7 text-xs font-medium border transition-colors bg-accent text-accent-foreground border-transparent inline-flex items-center">
+          Nodes
+        </span>
         <Link
           href="/fleet/overview"
           className="rounded-full px-3 h-7 text-xs font-medium border transition-colors bg-transparent text-muted-foreground border-border hover:bg-muted inline-flex items-center"
         >
           Overview
         </Link>
-        <span className="rounded-full px-3 h-7 text-xs font-medium border transition-colors bg-accent text-accent-foreground border-transparent inline-flex items-center">
-          Nodes
-        </span>
       </div>
 
       {/* Toolbar — shown when not loading and nodes exist or filters active */}

src/app/(dashboard)/pipelines/[id]/page.tsx

@@ -33,7 +33,6 @@ import { ComponentPalette } from "@/components/flow/component-palette";
 import { FlowCanvas } from "@/components/flow/flow-canvas";
 import { FlowToolbar } from "@/components/flow/flow-toolbar";
 import { AiPipelineDialog } from "@/components/flow/ai-pipeline-dialog";
-import { AiDebugPanel } from "@/components/flow/ai-debug-panel";
 import { DetailPanel } from "@/components/flow/detail-panel";
 import { DeployDialog } from "@/components/flow/deploy-dialog";
 import { SaveTemplateDialog } from "@/components/flow/save-template-dialog";
@@ -128,7 +127,6 @@ function PipelineBuilderInner({ pipelineId }: { pipelineId: string }) {
   const [metricsOpen, setMetricsOpen] = useState(false);
   const [logsOpen, setLogsOpen] = useState(false);
   const [aiDialogOpen, setAiDialogOpen] = useState(false);
-  const [debugPanelOpen, setDebugPanelOpen] = useState(false);
 
   const selectedTeamId = useTeamStore((s) => s.selectedTeamId);
   const teamQuery = useQuery(
@@ -202,14 +200,27 @@ function PipelineBuilderInner({ pipelineId }: { pipelineId: string }) {
     ),
   );
 
-  // Lightweight check for recent errors (for toolbar badge) — 24h window
-  const [errorCheckSince] = useState(
-    () => new Date(Date.now() - 24 * 60 * 60 * 1000),
-  );
+  // Compute session start from minimum uptime across all running nodes.
+  // Use dataUpdatedAt (stable timestamp from React Query) instead of Date.now()
+  // to satisfy react-hooks/purity (no impure calls) and avoid useEffect+setState.
+  const sessionStart = useMemo(() => {
+    const statuses = pipelineQuery.data?.nodeStatuses;
+    if (!statuses || statuses.length === 0) return null;
+    const uptimes = statuses
+      .filter((s: { status: string; uptimeSeconds: number | null }) =>
+        s.status === "RUNNING" && s.uptimeSeconds != null
+      )
+      .map((s: { uptimeSeconds: number | null }) => s.uptimeSeconds!);
+    if (uptimes.length === 0) return null;
+    const minUptime = Math.min(...uptimes);
+    return new Date(pipelineQuery.dataUpdatedAt - minUptime * 1000);
+  }, [pipelineQuery.data?.nodeStatuses, pipelineQuery.dataUpdatedAt]);
+
+  // Lightweight check for recent errors (for toolbar badge) — scoped to current session
   const recentErrorsQuery = useQuery(
     trpc.pipeline.logs.queryOptions(
-      { pipelineId, levels: ["ERROR"], limit: 1, since: errorCheckSince },
-      { enabled: !!isDeployed && !logsOpen, refetchInterval: 10000 },
+      { pipelineId, levels: ["ERROR"], limit: 1, since: sessionStart! },
+      { enabled: !!isDeployed && !logsOpen && !!sessionStart, refetchInterval: 10000 },
     ),
   );
   const hasRecentErrors = (recentErrorsQuery.data?.items?.length ?? 0) > 0;
@@ -464,7 +475,6 @@ function PipelineBuilderInner({ pipelineId }: { pipelineId: string }) {
             onDiscardChanges={() => setDiscardOpen(true)}
             aiEnabled={aiEnabled}
             onAiOpen={() => setAiDialogOpen(true)}
-            onDebugOpen={() => setDebugPanelOpen(true)}
             deployedVersionNumber={pipelineQuery.data?.deployedVersionNumber}
           />
         </div>
@@ -582,13 +592,6 @@ function PipelineBuilderInner({ pipelineId }: { pipelineId: string }) {
           onOpenChange={setAiDialogOpen}
           pipelineId={pipelineId}
           environmentName={pipelineQuery.data?.environment?.name}
-        />
-      )}
-      {aiEnabled && (
-        <AiDebugPanel
-          open={debugPanelOpen}
-          onOpenChange={setDebugPanelOpen}
-          pipelineId={pipelineId}
           currentYaml={currentYaml}
         />
       )}

src/app/(dashboard)/pipelines/page.tsx

@@ -124,6 +124,15 @@ function getReductionPercent(totals: {
   return Math.max(0, (1 - evOut / evIn) * 100);
 }
 
+function formatUptime(seconds: number | null): string {
+  if (seconds == null) return "\u2014";
+  if (seconds < 60) return `${seconds}s`;
+  if (seconds < 3600) return `${Math.floor(seconds / 60)}m`;
+  if (seconds < 86400)
+    return `${Math.floor(seconds / 3600)}h ${Math.floor((seconds % 3600) / 60)}m`;
+  return `${Math.floor(seconds / 86400)}d ${Math.floor((seconds % 86400) / 3600)}h`;
+}
+
 /** Derive display status string for a pipeline row. */
 function derivePipelineStatus(
   pipeline: { isDraft: boolean; nodeStatuses: Array<{ status: string }> },
@@ -587,6 +596,7 @@ export default function PipelinesPage() {
                 currentDirection={sortDirection}
                 onSort={handleSort}
               />
+              <TableHead className="text-right">Uptime</TableHead>
               <TableHead className="text-center">Health</TableHead>
               <SortableHeader
                 label="Events/sec In"
@@ -758,6 +768,10 @@ export default function PipelinesPage() {
                       )}
                     </div>
                   </TableCell>
+                  {/* Uptime */}
+                  <TableCell className="text-right font-mono text-sm tabular-nums text-muted-foreground">
+                    {formatUptime(pipeline.minUptimeSeconds)}
+                  </TableCell>
                   {/* Health — batch data instead of per-row query */}
                   <TableCell className="text-center">
                     {pipeline.isDraft ? (