perf: reduce re-renders, fix mobile keyboard handling, add chunk load recovery, and improve PATH management (#1028)

* fix: exclude file content from reverted prompt text

Revert and fork now restore only the user's original prompt, not server-injected file content
Uses existing isSyntheticPart helper for type-safe filtering

* fix: keep scrollbar visible when hovering over thumb

* fix: prevent ESC abort from triggering when terminal is focused

* fix: pass directory to permission/question reply calls so approvals actually resolve

* fix: default model selection not responding after Base UI migration

* fix: prevent modal content from shifting and clipping footer buttons

* fix: improve session switching performance and add sub-agent export with prompt collapse

Defer viewport anchor saving to eliminate ~800ms UI freeze when switching sessions
Add export dialog to include sub-agent tasks recursively in markdown export
Add collapse chevron button for expanded user prompts in sticky header

* fix: resolve sidebar scroll and TDZ crash in session sidebar

* perf: reduce CPU overhead and re-renders across chat, layout, and settings

* fix: position collapse button at top of message and prevent ESC abort in terminal

* fix: position collapse button at top and add padding only when expanded

* refactor: extract shared PATH utilities and mobile keyboard hook

* refactor: import shared path-utils in electron, use module-level style constants

- Electron now imports pathLooksUserConfigured/mergePathValues from
  shared path-utils.js instead of inline duplication
- ToolPart collapsedCustomStyle moved from useMemo([]) to module const

* fix: resolve remaining merge conflicts and type errors

- Remove duplicate variable declarations in SessionNodeItem
- Remove orphaned export callback body from conflict resolution
- Fix HelpDialog description -> descriptionKey (i18n rename)

* fix: resolve type-check and lint errors in session-actions.test.ts

- Added missing bun:test type declarations (beforeEach, mock, mock.module)
- Removed unused State import
- Replaced 'as any' casts with proper OpencodeClient and ChildStoreManager types
- Added eslint-disable for unused _ parameter in mock function

* fix PR 1028 export and PATH edge cases

* fix startup retry exhaustion state

* remove opencode package lock change

* fix sub-session rename cancellation

---------

Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/components/session/SessionSidebar.tsx

@@ -45,6 +45,7 @@ import { SidebarFooter } from './sidebar/SidebarFooter';
 import { SidebarProjectsList } from './sidebar/SidebarProjectsList';
 import { SessionNodeItem } from './sidebar/SessionNodeItem';
 import { useUpdateStore } from '@/stores/useUpdateStore';
+import { useShallow } from 'zustand/react/shallow';
 import { listProjectWorktrees } from '@/lib/worktrees/worktreeManager';
 import type { WorktreeMetadata } from '@/types/worktree';
 import type { SortableDragHandleProps } from './sidebar/sortableItems';
@@ -290,7 +291,18 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
   const worktreeMetadata = useSessionUIStore((state) => state.worktreeMetadata);
   const availableWorktreesByProject = useSessionUIStore((state) => state.availableWorktreesByProject);
   const openNewSessionDraft = useSessionUIStore((state) => state.openNewSessionDraft);
-  const updateStore = useUpdateStore();
+  const updateStore = useUpdateStore(useShallow((s) => ({
+    checkForUpdates: s.checkForUpdates,
+    available: s.available,
+    runtimeType: s.runtimeType,
+    info: s.info,
+    downloading: s.downloading,
+    downloaded: s.downloaded,
+    progress: s.progress,
+    error: s.error,
+    downloadUpdate: s.downloadUpdate,
+    restartToUpdate: s.restartToUpdate,
+  })));
 
   const sessions = React.useMemo(() => {
     const liveById = new Map(liveSessions.map((session) => [session.id, session]));