Redesign the management home page's KPIs and charts

Drop renewal rate from the top KPI bar; split "Upcoming events" in half
and add a "News" overview beside it (published items only, everyone
can see it, same as events). Signups-per-month, club fee status, and
renewal rate (now a pie chart matching the fee status one, not a bare
stat box) move into their own row and become admin-only like the fee
chart already was. The bottom stat-group row now sizes its columns to
how many groups actually render, instead of leaving a blank slot where
Shop would be for non-admins.

static/css/app.css

@@ -3967,6 +3967,16 @@
       grid-template-columns: repeat(2, minmax(0, 1fr));
     }
   }
+  .lg\:grid-cols-3 {
+    @media (width >= 64rem) {
+      grid-template-columns: repeat(3, minmax(0, 1fr));
+    }
+  }
+  .lg\:grid-cols-5 {
+    @media (width >= 64rem) {
+      grid-template-columns: repeat(5, minmax(0, 1fr));
+    }
+  }
   .lg\:grid-cols-6 {
     @media (width >= 64rem) {
       grid-template-columns: repeat(6, minmax(0, 1fr));