Console panel, collapsible panels, Add on the Members panel

- Server settings > Console sends a raw console command for staff with @css/rcon
  (POST /api/admin/rcon). It doesn't wait for the server; the output is only logged.
- Staff & ranks and Server settings panels fold up by clicking their heads. All but
  Ranks and Server start folded; a folded Ranks panel shows the selected rank.
- The Members panel has an Add button that opens Add staff with that rank picked.
- The public rank log shows a rank being given as Promoted and taken away as Demoted.

internal/web/assets/public.js

@@ -181,12 +181,13 @@ async function staff() {
   loadRankLog();
 }
 
+// The database's added/removed are shown as promotions/demotions too: gaining or losing a rank.
 const RANK_CHANGE = {
-  added: ["Joined", "green"],
+  added: ["Promoted", "green"],
   promoted: ["Promoted", "green"],
   demoted: ["Demoted", "amber"],
   changed: ["Moved", ""],
-  removed: ["Removed", "red"],
+  removed: ["Demoted", "amber"],
 };
 
 async function loadRankLog() {