Cleaner carousels and an easier language menu

Two small quality-of-life fixes this time. On phones and tablets, the arrows on the two-row carousels (Guide Lab, Games and the Dashboard Color picker) used to sit right on top of the cover art. They now live in the gap between the two rows, at the left and right edges, so every cover stays fully visible. The covers are exactly the same size as before, and on a wide screen, where everything already fits, nothing changes. The Language section in the account menu now shows every language CompletionLab is available in, in a short list you can scroll. Each language is written in its own language, with its name in yours underneath, and the list opens on the one you're using. "View all languages" underneath takes you to the full Language page, which is also where the translation percentages now live.