Aggiunge monitoraggio ops: health check, log scanner, dashboard e notifiche.

Introduce incidenti con dedup, job Sidekiq ogni 3 min, scan log cron, /up/deep,
dashboard /admin/ops e push ntfy; include Sentry opzionale e fix test suite.

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

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

@@ -0,0 +1,83 @@
+<% content_for :body_class, "admin-body" %>
+
+<section class="kpi-grid">
+  <div class="kpi-card <%= @summary[:open_critical].positive? ? 'kpi-card--danger' : 'kpi-card--accent' %>">
+    <div class="kpi-label">Critici aperti</div>
+    <div class="kpi-value"><%= @summary[:open_critical] %></div>
+  </div>
+  <div class="kpi-card">
+    <div class="kpi-label">Warning aperti</div>
+    <div class="kpi-value"><%= @summary[:open_warning] %></div>
+  </div>
+  <div class="kpi-card">
+    <div class="kpi-label">Totale aperti</div>
+    <div class="kpi-value"><%= @summary[:open_total] %></div>
+  </div>
+</section>
+
+<div class="panel" style="margin-bottom:1.5rem">
+  <h2>Incidenti aperti</h2>
+  <% if @open_incidents.any? %>
+    <table class="admin-table">
+      <thead>
+        <tr>
+          <th>Severità</th>
+          <th>Tipo</th>
+          <th>Titolo</th>
+          <th>Occ.</th>
+          <th>Ultimo</th>
+          <th></th>
+        </tr>
+      </thead>
+      <tbody>
+        <% @open_incidents.each do |inc| %>
+          <tr>
+            <td><span class="badge badge--<%= inc.severity == 'critical' ? 'live' : 'paused' %>"><%= inc.severity %></span></td>
+            <td class="muted"><%= inc.kind %></td>
+            <td>
+              <strong><%= inc.title %></strong>
+              <% if inc.message.present? %>
+                <div class="muted" style="font-size:0.85rem;margin-top:0.25rem"><%= truncate(inc.message, length: 120) %></div>
+              <% end %>
+            </td>
+            <td><%= inc.occurrence_count %></td>
+            <td class="muted"><%= inc.last_seen_at&.strftime("%d/%m %H:%M") %></td>
+            <td class="admin-actions">
+              <% unless inc.status == 'acknowledged' %>
+                <%= button_to "Preso in carico", acknowledge_admin_op_path(inc), method: :post, class: "admin-btn admin-btn--sm" %>
+              <% end %>
+              <%= button_to "Risolvi", resolve_admin_op_path(inc), method: :post, class: "admin-btn admin-btn--sm" %>
+              <%= button_to "Mute 24h", mute_admin_op_path(inc), method: :post, class: "admin-btn admin-btn--sm admin-btn--outline" %>
+            </td>
+          </tr>
+        <% end %>
+      </tbody>
+    </table>
+  <% else %>
+    <p class="empty">Nessun incidente aperto. La piattaforma risulta sana.</p>
+  <% end %>
+</div>
+
+<div class="panel">
+  <h2>Risolti (ultimi 30 giorni)</h2>
+  <% if @resolved_incidents.any? %>
+    <table class="admin-table">
+      <thead>
+        <tr><th>Severità</th><th>Tipo</th><th>Titolo</th><th>Occ.</th><th>Risolto</th></tr>
+      </thead>
+      <tbody>
+        <% @resolved_incidents.each do |inc| %>
+          <tr>
+            <td><span class="badge badge--connecting"><%= inc.severity %></span></td>
+            <td class="muted"><%= inc.kind %></td>
+            <td><%= inc.title %></td>
+            <td><%= inc.occurrence_count %></td>
+            <td class="muted"><%= inc.updated_at.strftime("%d/%m %H:%M") %></td>
+          </tr>
+        <% end %>
+      </tbody>
+    </table>
+  <% else %>
+    <p class="empty">Nessun incidente risolto di recente.</p>
+  <% end %>
+</div>