- Update UI_LAYOUT.md with comprehensive panel taxonomy - Document Nav Panel, Filter Panel, Detail Panel, Chat Dock specs - Add panel header behavior (bottom-docked for left panels) - Add responsive breakpoints with panel folding summary - Create PanelHeader widget with dockToBottom option - Create FilterPanel widget for data filtering sidebars - Refactor Control Room to use FilterPanel - Remove external links from sidebar (cleanup) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>