Add a 3-state theme toggle in folder selection and instance tabs, and update tokens/styles so light mode has readable contrast. Sync MUI surfaces and Shiki highlighting to CSS variables to prevent stale colors when switching themes.
Adds an optional session filter bar to the left sidebar with title search across parent/child sessions and a scoped Select All. Introduces multi-select checkboxes, bulk delete with clear selection controls, and confirmation dialogs for both single and bulk deletions using the existing alert dialog flow. Updates session i18n strings across supported locales.
Converts hardcoded UI copy to i18n keys across the app, adds global translation for non-component modules, and splits the English catalog into feature modules with duplicate-key detection.
Cmd+Shift+[ and Cmd+Shift+] now cycle through visible sessions only (parents + expanded children) and no longer include Instance Info. Sidebar session list auto-scrolls to keep the active session row in view.
Show sessions as parent/child threads with expand/collapse and improved agent row styling. Keep a 5-session cache to avoid refetching messages when switching between recently visited sessions.
Implements a unified permission notification UI that adapts to different runtime
environments (Electron desktop vs web browser) with distinct visual presentations.
## What Changed
### New Components
- `permission-notification-banner.tsx`: Adaptive notification component
* Electron (desktop): Full banner with "⚠️ Approval Required" text and count badge
* Web browser (portrait): Circular indicator badge showing pending count
- `permission-approval-modal.tsx`: Interactive modal for reviewing/approving permissions
* Displays permission type, detailed message, and diff viewer for file changes
* Keyboard shortcuts: Enter (allow once), A (always), D (deny), Esc (close)
* Queue management with "X of Y" counter for multiple pending permissions
- `permission-notification.css`: Comprehensive styling with pulsing animations
### Integration
- Updated `instance-shell2.tsx`:
* Added banner to desktop center toolbar (next to Command Palette)
* Added banner to mobile/phone layout center section
* Added modal component for permission approval workflow
- Updated `controls.css`: Imported new permission notification styles
## Why This Change
**Before**: Permission requests had no visual indicator in the UI, making it
difficult for users to know when agent/subagent actions required approval.
**After**: Users receive clear, persistent visual notifications with:
- Pulsing animation to draw attention
- Environment-appropriate UI (full banner on desktop, compact badge on web)
- Click-to-review workflow with full permission details
## Benefits
1. **Better UX**: Users immediately see when permissions need approval
2. **Responsive Design**: Adapts to desktop (Electron) and web browser contexts
3. **Accessible**: Proper ARIA labels, keyboard shortcuts, and focus management
4. **Queue Management**: Handles multiple pending permissions gracefully
5. **Contextual Information**: Shows diffs for file changes, permission types, etc.
## Impact
- **No Breaking Changes**: Purely additive feature
- **Build**: ✅ Verified successful build
- **Testing**: ✅ Tested in Electron app and web browser
