docs: update the wiki for 1.0.0-beta.6: new pages, screenshots and corrections
docs: GitHub update checks in the privacy notes; Settings › General › Updates
docs: the repository is now open-wallpaper-engine-mac
docs: standard Markdown links everywhere, and link the Steam login mentions
docs: table links use Markdown links, so the pipe doesn't split the cell
docs: link repo files on the feature branch, the dark app icon on Home, and fix a dead profile link
docs: Open Wallpaper Engine wiki (user and developer guides)
Initial Home page