feat: add approval ui for join requests

lib/mv_web/page_paths.ex

@@ -9,6 +9,7 @@ defmodule MvWeb.PagePaths do
   # Sidebar top-level menu paths
   @members "/members"
   @statistics "/statistics"
+  @join_requests "/join_requests"
 
   # Administration submenu paths (all must match router)
   @users "/users"
@@ -35,6 +36,9 @@ defmodule MvWeb.PagePaths do
   @doc "Path for Statistics page (sidebar and page permission check)."
   def statistics, do: @statistics
 
+  @doc "Path for Join Requests approval UI (sidebar and page permission check)."
+  def join_requests, do: @join_requests
+
   @doc "Paths for Administration menu; show group if user can access any of these."
   def admin_menu_paths, do: @admin_page_paths