bulma (call): add a button for screen sharing: - add a button for screen sharing, only on desktop - split `muted` state to `inactive` and `muted` where `muted` is only about the color - use the `inactive` state with an other color (in `screen-off` class) to indicate when screen is not shared rel 432

{
    "js": {
        "package": {
            "dependencies": {
                "bulma": ">= 0.9.0"
            }
        }
    }
}