privmsg: add highlighted point redeem bool

[Ganom]

This adds a simple bool for when a user redeems the "Highlighted Message" reward using channel points.

[Ganom]

I believe that's how it currently is, here is the full excerpt

                case (int)Tags.MsgId:
                    switch (tagValue.Sum())
                    {
                        case 2516:
                            gigantified = true;
                            break;

                        case 1939:
                            highlighted = true;
                            break;

                        case 1621:
                            animated = true;
                            break;
                    }
                    break;

[occluder]

Ah yes you are right, I did not expand the diff enough to see the scope. Looks good, thank you for contributing!