Unified settings pane

[cpfair]

Rather than having settings spread across modals, dropdowns, tooltips, etc, where nobody can find them, why not something like this? (MS Paint mockups, thanks @ysofi for the idea)

Closed (reduced top-bar clutter - just the universal "settings" gear):

Open:

The existing settings modal would be eliminated, along with its entry in the left nav. This does move stuff like reading mode and night mode from 1 click to 2 clicks, but it eliminates confusion over where all the settings are, and re-surfaces the translation and recitation options that are very well hidden at the moment. It also adds Yet Another Side-Menu - which I think is the lesser of two evils compared to the current modal settings screen and mystery-meat option buttons.