Aggiunge i tornei con hub, pagina pubblica e tabellone per semifinali e finali.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/views/public/tournaments/_tab_struttura.html.erb

@@ -0,0 +1,34 @@
+<div class="card">
+  <p style="color:#888"><%= t("tournaments.form.formats.#{@tournament.format_kind}") %></p>
+
+  <% if @tournament.uses_groups? %>
+    <h2><%= t("tournaments.hub.tabs.struttura") %></h2>
+    <ul>
+      <% @groups.each do |group| %>
+        <li style="margin-bottom:8px">
+          <%= group.name %>
+          <% if @writable %>
+            <%= button_to t("matches.index.delete"), public_tournament_group_path(@tournament, group),
+                  method: :delete, class: "btn btn-secondary", style: "padding:4px 10px;font-size:0.8rem;display:inline",
+                  form: { data: { turbo_confirm: group.name }, style: "display:inline" } %>
+          <% end %>
+        </li>
+      <% end %>
+    </ul>
+    <% if @writable %>
+      <%= form_with url: public_tournament_groups_path(@tournament), method: :post do %>
+        <%= text_field_tag "tournament_group[name]", nil, placeholder: t("tournaments.hub.add_group") %>
+        <%= submit_tag t("tournaments.hub.add_group"), class: "btn btn-secondary" %>
+      <% end %>
+    <% end %>
+  <% end %>
+
+  <% if @tournament.uses_knockout? %>
+    <h2 style="margin-top:20px"><%= t("tournaments.hub.tabs.tabellone") %></h2>
+    <ul>
+      <% @rounds.each do |round| %>
+        <li><%= round.name %></li>
+      <% end %>
+    </ul>
+  <% end %>
+</div>