Bug fixes and enhancements

The gamma9 build has been deployed, this includes the following changes:

• Tidied up service calls for fetching leaderboards and the daily challenge, which means a slightly quicker UI.

• Fixed uncommon case where the transition or engine sound would loop continuously.

• Tapping the control key will play a quick red burst animation on top of the mouse cursor. Handy if you've lost it!

• Fixed inconsistencies in the German translation.

• Removed one-frame snap when continuing a scored game.

• Screenshot and GIF save notification messages no longer persist past their useful lifetime.