- Display images from read tool results (base64 encoded)
- Add ellipsis for truncated tree entries
- Make mobile hamburger button more subtle
- Add X close button in sidebar header on mobile
- Hide hamburger when sidebar is open
- Add deriveExportColors() to compute page/card/info backgrounds from userMessageBg
- Use luminance detection to adapt colors for light/dark themes
- Use info-bg for model-change, compaction, system-prompt sections
- Use selectedBg for hover states and summary backgrounds
- Add scroll-to-message with highlight when clicking tree nodes
- Fix mobile overlay to close sidebar on click
- Wider sidebar (400px) with search and filter controls
- Add tree sidebar with search and filter (Default/All/Labels)
- Client-side markdown/syntax highlighting via vendored marked.js + highlight.js
- Base64 encode session data to avoid escaping issues
- Reuse theme.ts color tokens via getResolvedThemeColors()
- Sticky sidebar, responsive mobile layout with overlay
- Click tree node to scroll to message
- Keyboard shortcuts: Esc to reset, Ctrl/Cmd+F to search