Replaced the existing settings button with a new `OptionsButton` component.
This new component integrates a menu for more actions, providing an
extensible and accessible interface.
Refactoring will follow to enhance code maintainability.
A legacy style was introduced to keep visual coherence with the other controls
from the controls bar. It's temporary, until we redesign the whole bar.
It doesn't match pixel-perfect the legacy styles.
A new public Tchap chan was created. All users, and not only beta users,
can now join it using the link in the menu, and reach us.
1715ec10dd