Sound for game-start countdown

[sprunk]

Kingstad wants sounds for when the game is about to start (I assume ideally they would work when alt-tabbed as well). Infra support for this exists since recently (see #5372).

[Licho1]

There is also a way to invoke notification. The chobby wrapper has a method that can invoke alert including flashing window. Ideally we would like a combination of sound + system alert.
Should it ignore sound settings too?

[sprunk]

Unsure, though it could always be a series of options:

• notify on game start
• notify even if sound is muted
• notify even if just spectating