UX polish and refactor

- Visual polish for the settings page, keyboard shortcuts page, and outdenting tooltip
- Tweak copy throughout the app to make it a little simpler
- Add the ability to fetch the name of the meta key (i.e. Cmd or Ctrl) so it can be displayed to the user
- Make it possible to Cancel out of editing a keyboard shortcut, rather than the only option being to Save

resources/css/tooltip.css

@@ -658,3 +658,7 @@
 .tippy-wrapper {
   background-color: var(--ls-tertiary-background-color);
 }
+
+.tippy-hover {
+  cursor: pointer;
+}