Members and bookmarks were 266px, the gallery 320, the threads list 340,
a thread and widgets 360. Swapping panels resized the room view, so the
header icons slid sideways (74px for members -> threads) and a second
click on the same spot opened Widgets instead of closing the panel. All
six now use SIDE_PANEL_WIDTH (340px, styles/sidePanel.ts).
Fixes#263
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5