Needed to revive the lobby tests.

refactor overflow menu to use ContextMenu component
refactor toolboxItem to use ContextMenuItem when needed

Fixes issue where the menu would disappear on dominant speaker change

Update video thumbnail design
Update design of indicators
In filmstrip view move Screen Sharing indicator to the top
Removed dominant speaker indicator
Use ContextMenu component for the connection stats popover
Combine Remove video menu and Meeting participant context menu into one component
Moved some styles from SCSS to JSS
Fix mobile avatars too big
Fix mobile horizontal scroll
Created button for Send to breakout room action

- implement breakout-rooms
- integrated into the participants panel
- managed by moderators
- moderators can send participants to breakout-rooms
- participants can join breakout rooms by themselve
- participants can leave breakout rooms anytime

Co-authored-by: Robert Pintilii <robert.pin9@gmail.com>
Co-authored-by: Saúl Ibarra Corretgé <saghul@jitsi.org>

Clicking on an item when the popup drawer is displayed would keep it open.
Now clicking on any item should automatically close the drawer.

Popup was also refactored and no longer uses refs.

Created Reusable components for:
- ListItem - used by participants list and lobby participants list
- ContextMenu - used by participant context menu and advanced moderation context menu
- Quick action button - used by quick action buttons on participant list items

Moved participants custom theme to base/components/themes

Created reusable button component for all participants pane buttons (Invite, Mute All, More)

Moved web components to web folder

Moved all styles from Styled Components to JSS

Fixed accessibility labels for some buttons

Removed unused code

Updated all styles to use theme tokens