Keep large sidebars responsive (#1966)

* perf(app): keep large sidebars responsive

Sidebar rows rescanned every agent for each session update, multiplying work with both workspace and agent count. Build workspace activity once and share the derived sidebar model so updates scale with the underlying collections.

* test(app): use valid agent fixture for workspace restore

* refactor(app): keep sidebar model surface focused

packages/app/src/components/sidebar-workspace-list.tsx

@@ -68,7 +68,6 @@ import {
   shouldShowSidebarHostLabels,
   useSidebarWorkspaceEntry,
   type SidebarProjectEntry,
-  type SidebarStatusWorkspacePlacement,
   type SidebarWorkspaceEntry,
   type SidebarWorkspacePlacement,
 } from "@/hooks/use-sidebar-workspaces-list";
@@ -93,6 +92,7 @@ import { shouldRenderSyncedStatusLoader } from "@/utils/status-loader";
 import { isEmphasizedStatusDotBucket } from "@/utils/status-dot-color";
 import type { SidebarStateBucket } from "@/utils/sidebar-agent-state";
 import { SidebarStatusWorkspaceList } from "@/components/sidebar/sidebar-status-list";
+import type { StatusGroup } from "@/hooks/sidebar-status-view-model";
 import {
   SidebarWorkspaceRowFrame,
   SidebarWorkspaceRowContent,
@@ -228,7 +228,7 @@ function selectionForSelectedWorkspace(
 }
 
 interface SidebarWorkspaceListProps {
-  statusWorkspacePlacements: SidebarStatusWorkspacePlacement[];
+  statusGroups: StatusGroup[];
   projects: SidebarProjectEntry[];
   projectNamesByKey: Map<string, string>;
   collapsedProjectKeys: ReadonlySet<string>;
@@ -2166,7 +2166,7 @@ function areProjectBlockSelectionsEqual(
 const MemoProjectBlock = memo(ProjectBlock, areProjectBlockPropsEqual);
 
 export function SidebarWorkspaceList({
-  statusWorkspacePlacements,
+  statusGroups,
   projects,
   projectNamesByKey,
   collapsedProjectKeys,
@@ -2196,7 +2196,7 @@ export function SidebarWorkspaceList({
   const content =
     groupMode === "status" ? (
       <SidebarStatusModeWrapper
-        statusWorkspacePlacements={statusWorkspacePlacements}
+        statusGroups={statusGroups}
         projectNamesByKey={projectNamesByKey}
         shortcutIndexByWorkspaceKey={shortcutIndexByWorkspaceKey}
         onWorkspacePress={onWorkspacePress}
@@ -2224,14 +2224,14 @@ export function SidebarWorkspaceList({
 }
 
 function SidebarStatusModeWrapper({
-  statusWorkspacePlacements,
+  statusGroups,
   projectNamesByKey,
   shortcutIndexByWorkspaceKey: _projectShortcutIndex,
   onWorkspacePress,
   hostLabelByServerId,
   showHostLabels,
 }: {
-  statusWorkspacePlacements: SidebarStatusWorkspacePlacement[];
+  statusGroups: StatusGroup[];
   projectNamesByKey: Map<string, string>;
   shortcutIndexByWorkspaceKey: Map<string, number>;
   onWorkspacePress?: () => void;
@@ -2242,7 +2242,7 @@ function SidebarStatusModeWrapper({
 
   return (
     <SidebarStatusWorkspaceList
-      workspaces={statusWorkspacePlacements}
+      groups={statusGroups}
       projectNamesByKey={projectNamesByKey}
       shortcutIndexByWorkspaceKey={_projectShortcutIndex}
       showShortcutBadges={showShortcutBadges}
@@ -2268,7 +2268,7 @@ function ProjectModeList({
   supportsMultiplicityByServerId,
 }: Omit<
   SidebarWorkspaceListProps,
-  "statusWorkspacePlacements" | "projectNamesByKey" | "groupMode" | "isRefreshing" | "onRefresh"
+  "statusGroups" | "projectNamesByKey" | "groupMode" | "isRefreshing" | "onRefresh"
 > & {
   pathname: string;
   hostLabelByServerId: ReadonlyMap<string, string>;