Enhancement: settings reorganization & improvements, separate admin section (#4251)

* Separate admin / manage sections

* Move mail settings to its own component

* Move users and groups to its own component

* Move default permissions to its own settings tab

* Unify list styling, add tour step, refactor components

* Only patch saved views that have changed on settings save

* Update messages.xlf

* Remove unused methods in settings.component.ts

* Drop admin section to bottom of sidebar, cleanup outdated, add docs link to dropdown

* Better visually unify management list & other list pages

src-ui/src/styles.scss

@@ -50,6 +50,11 @@ svg.logo {
   color: var(--bs-body-color);
 }
 
+.list-group-item .btn-link,
+table .btn-link {
+  font-size: 1em;
+}
+
 .bg-body {
   background-color: var(--bs-body-bg);
 }