bingo: operational-only view of the card

The card mixes facilities in service with construction projects (Sber
Balakovo at #1, MOS7, MOS11, Yandex Vladimir-2), which is fine for a
bingo but not when you want to compare what actually runs today. Add a
toggle that builds the card from operational rows only, in the same
ranking, with bingo lines recomputed for that card. The filtered view is
noindex with canonical to the plain locale URL, so it does not compete
with the main page in search.

Assisted-by: Claude:opus-5

views/bingo/index.erb

@@ -2,11 +2,18 @@
 <main>
   <header>
     <h1><%= t(:lead) %> <span><%= t(:accent) %></span></h1>
-    <nav class="langs">
-      <% Bingo::LOCALES.each do |l| %>
-        <a href="/<%= l %>" hreflang="<%= l %>" lang="<%= l %>" <%== 'aria-current="page"' if l == @locale %>><%= l %></a>
-      <% end %>
-    </nav>
+    <div class="switches">
+      <nav class="toggle" aria-label="<%= t(:view_label) %>">
+        <% Bingo::VIEWS.each do |v| %>
+          <a href="<%= card_path(@locale, v) %>" rel="nofollow" <%== 'aria-current="page"' if v == @view %>><%= t(:"view_#{v}") %></a>
+        <% end %>
+      </nav>
+      <nav class="langs">
+        <% Bingo::LOCALES.each do |l| %>
+          <a href="<%= card_path(l) %>" hreflang="<%= l %>" lang="<%= l %>" <%== 'aria-current="page"' if l == @locale %>><%= l %></a>
+        <% end %>
+      </nav>
+    </div>
   </header>
 
   <p class="lead"><%= t(:desc) %></p>