Admin analytics: heatmap per device, anteprima staff e analisi costi.

Separa heatmap mobile/desktop, opt-out analytics per operatori, dashboard costi con KPI e trend mensili.

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

backend/app/views/admin/analytics/index.html.erb

@@ -5,6 +5,32 @@
   <p class="muted admin-page-sub"><%= t("admin.analytics.index.lead") %></p>
 </div>
 
+<section class="panel admin-analytics-preview">
+  <h3><%= t("admin.analytics.preview.title") %></h3>
+  <p class="muted admin-table-sub"><%= t("admin.analytics.preview.lead") %></p>
+  <% if @analytics_preview_active %>
+    <p class="admin-analytics-preview__status"><%= t("admin.analytics.preview.active") %></p>
+    <div class="admin-filter-actions">
+      <%= button_to t("admin.analytics.preview.disable"),
+            admin_analytics_preview_path,
+            method: :delete,
+            class: "admin-btn admin-btn--outline admin-btn--sm" %>
+      <%= link_to t("admin.analytics.preview.open_site"),
+            root_path,
+            class: "admin-btn admin-btn--primary admin-btn--sm",
+            target: "_blank",
+            rel: "noopener" %>
+    </div>
+  <% else %>
+    <div class="admin-filter-actions">
+      <%= button_to t("admin.analytics.preview.enable"),
+            admin_analytics_preview_path(return_to: root_path),
+            method: :post,
+            class: "admin-btn admin-btn--primary admin-btn--sm" %>
+    </div>
+  <% end %>
+</section>
+
 <div class="panel admin-sessions-filters">
   <%= form_with url: admin_analytics_path, method: :get, local: true, class: "admin-filter-form" do %>
     <div class="admin-filter-grid">
@@ -58,8 +84,9 @@
               <td class="muted"><%= avg %>%</td>
               <td class="muted"><%= row[:max_scroll] %>%</td>
               <td>
-                <%= link_to t("admin.analytics.index.heatmap"),
-                      admin_analytics_page_path(page_path: row[:page_path], from: @filters[:from], to: @filters[:to], device: @filters[:device]) %>
+                <% heatmap_params = { page_path: row[:page_path], from: @filters[:from], to: @filters[:to] } %>
+                <% heatmap_params[:device] = @filters[:device] if @filters[:device].present? %>
+                <%= link_to t("admin.analytics.index.heatmap"), admin_analytics_page_path(heatmap_params) %>
               </td>
             </tr>
           <% end %>