Fixes and improvements across profiles, room navigation, and the emoji/sticker picker:
- Fix stale scroll position and HTML bio rendering when navigating profiles
- Fix Alt+Up/Down room navigation when no room is currently selected
- Add a "Reactions" dialog for viewing who reacted with what
- Add a "View Devices" link to a room member's profile
- Fix emoji picker tiles not filling their full clickable area
- Fix the custom emoji/sticker picker loading full-resolution images
- Fix "Create New Pack" wrapping and a double scrollbar in the devices dialog
- Fix /me messages with a mention pill wrapping onto a second line
- Make the Forward dialog's body/attachment toggles clickable anywhere
- Keep the room list's blurred-avatar backdrop bundled regardless of the old room list flag
