refactor(sidebar): rebuild footer as priority-driven Ops Pulse strip (#1178)

* refactor(sidebar): rebuild footer as priority-driven Ops Pulse strip

Replace the simple notification ticker with a derived activity summary that
picks one of six states (active-op, failure, automation, recent-event,
quiet-live, disconnected) and routes per-state clicks to logs, schedules,
or activity. The hook owns the cascade; the component is pure presentation;
EditorLayout owns wiring.

Failure detection covers unread errors in the last 24h; recent-event is
limited to non-error stack notifications in the last hour; automation reads
the next /scheduled-tasks?action=update run and a debounced state-invalidate
listener; the deploy-panel composite key is used for elapsed-time tracking
so close-then-immediately-reopen counts as a new session.

* refactor(sidebar): apply Ops Pulse audit fixes

- countEnabledAutoUpdates now defaults missing autoUpdateSettings entries to
  enabled, matching the backend's getStackAutoUpdateSettingsForNode contract.
  Previously the automation state could not render even with the documented
  per-row default-true.
- findFailure now requires a stack_name so the sidebar does not select a
  system-level error whose click would no-op through navigateToNotification.
  System errors continue to surface via the top-bar NotificationPanel.
- DeployPanelState gains a monotonic sessionId sourced from the existing
  internal counter, and the new usePanelSessionStartedAt hook keys the
  elapsed-time tracker off it so a same-stack rerun always resets even when
  isOpen stays true across succeeded then preparing.
- buildConfig splits quiet-live out of the default and adds an exhaustiveness
  guard so future SidebarActivitySummary variants fail to compile.
- New unit tests cover the default-true aggregation, the same-stack session
  reset, the non-stack failure guard, and the useNextAutoUpdateRun debounce
  and cleanup paths. Frontend suite: 276 / 276 pass.

frontend/src/components/EditorLayout.tsx

@@ -1,4 +1,4 @@
-import { useEffect, useRef } from 'react';
+import { useCallback, useEffect, useMemo, useRef } from 'react';
 import { Button } from './ui/button';
 import { Plus } from 'lucide-react';
 import { UserProfileDropdown } from './UserProfileDropdown';
@@ -32,6 +32,10 @@ import { useDeployFeedback } from '@/context/DeployFeedbackContext';
 import { useTrivyStatus } from '@/hooks/useTrivyStatus';
 import { StackSidebar } from '@/components/sidebar/StackSidebar';
 import type { StackRowStatus } from '@/components/sidebar/stack-status-utils';
+import { useSidebarActivitySummary, countEnabledAutoUpdates } from '@/components/sidebar/useSidebarActivitySummary';
+import { useNextAutoUpdateRun } from '@/components/sidebar/useNextAutoUpdateRun';
+import { usePanelSessionStartedAt } from '@/components/sidebar/usePanelSessionStartedAt';
+import type { SidebarActivityAction } from '@/components/sidebar/SidebarActivityTicker';
 import { useComposeDiffPreviewEnabled } from '@/hooks/use-compose-diff-preview-enabled';
 import { toast } from '@/components/ui/toast-store';
 
@@ -39,7 +43,7 @@ export default function EditorLayout() {
   const { isAdmin, can } = useAuth();
   const { isPaid, license } = useLicense();
   const { status: trivy } = useTrivyStatus();
-  const { runWithLog } = useDeployFeedback();
+  const { runWithLog, panelState } = useDeployFeedback();
 
   const editorState = useEditorViewState();
   const {
@@ -64,6 +68,7 @@ export default function EditorLayout() {
 
   const stackListState = useStackListState();
   const {
+    files,
     selectedFile,
     isLoading,
     stackActions: stackActionMap,
@@ -71,6 +76,7 @@ export default function EditorLayout() {
     searchQuery, setSearchQuery,
     stackStatuses,
     stackLabelMap,
+    autoUpdateSettings,
     filterChip, setFilterChip,
     bulkMode,
     selectedFiles,
@@ -178,6 +184,40 @@ export default function EditorLayout() {
     pendingLogsRef,
   } = stackActions;
 
+  const panelStartedAt = usePanelSessionStartedAt(panelState);
+
+  const autoUpdateEnabledCount = useMemo(
+    () => countEnabledAutoUpdates(files, autoUpdateSettings),
+    [files, autoUpdateSettings],
+  );
+
+  const nextAutoUpdateRunAt = useNextAutoUpdateRun();
+  const activitySummary = useSidebarActivitySummary({
+    notifications,
+    tickerConnected,
+    panelState,
+    panelStartedAt,
+    autoUpdateEnabledCount,
+    totalStackCount: files.length,
+    nextAutoUpdateRunAt,
+  });
+
+  const handleActivityAction = useCallback((action: SidebarActivityAction) => {
+    switch (action.kind) {
+      case 'open-stack-notification':
+        stackActions.navigateToNotification(action.summary.notif);
+        return;
+      case 'open-auto-updates':
+        setActiveView('auto-updates');
+        return;
+      case 'open-activity':
+        setActiveView('global-observability');
+        return;
+      case 'noop':
+        return;
+    }
+  }, [stackActions, setActiveView]);
+
   const loadingAction = selectedFile ? (stackActionMap[selectedFile] ?? null) : null;
   const stackName = selectedFile || '';
 
@@ -303,9 +343,8 @@ export default function EditorLayout() {
             if (node) void stackActions.loadFileOnNode(node, file);
           },
         }}
-        notifications={notifications}
-        tickerConnected={tickerConnected}
-        onOpenActivity={() => setActiveView('global-observability')}
+        activitySummary={activitySummary}
+        onActivityAction={handleActivityAction}
         bulkMode={bulkMode}
         selectedFiles={selectedFiles}
         isPaid={isPaid}