Fix views/controllers/router: command palette, create form, admin views

- Consolidate the duplicated command palette to a single overlay + init in
  the footer; fix New Ticket to route to /ticket/create (was a 404 /create);
  keep the CSP nonce and all commands
- TicketController create(): trim title, require a non-empty description,
  and honor the posted status (validated against the canonical list) instead
  of silently discarding it
- UserActivityView: 'Active Users' counts only users active in the selected
  range, not every registered user
- layout_footer/DashboardView: local esc() now escapes quotes so values used
  in HTML attributes can't break out
- TicketView: comments tab badge shows the true total, not just page one
- layout_header: gate the 'View activity log' link behind the admin flag
- index.php: validate /admin/user-activity date params; anchor the legacy
  /ticket.php route; align the audit action-type whitelist with the dropdown
- ApiKeysView: correct the external API sample to /create_ticket_api.php

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

views/admin/UserActivityView.php

@@ -43,11 +43,23 @@ include __DIR__ . '/../../views/layout_header.php';
 
     <!-- Summary stats -->
     <?php if (!empty($userStats)) : ?>
+        <?php
+        // "Active" = users with >=1 tracked action within the selected date range.
+        // The query LEFT JOINs from all users, so $userStats includes zero-activity users.
+        $activeUsers = 0;
+        foreach ($userStats as $_u) {
+            $_activity = ($_u['tickets_created'] ?? 0) + ($_u['tickets_resolved'] ?? 0)
+                + ($_u['comments_added'] ?? 0) + ($_u['tickets_assigned'] ?? 0);
+            if ($_activity > 0) {
+                $activeUsers++;
+            }
+        }
+        ?>
     <div class="lt-stats-grid lt-mb-md">
       <div class="lt-stat-card">
         <div class="lt-stat-icon lt-text-cyan">[ # ]</div>
         <div class="lt-stat-info">
-          <div class="lt-stat-value"><?= count($userStats) ?></div>
+          <div class="lt-stat-value"><?= (int)$activeUsers ?></div>
           <div class="lt-stat-label">Active Users</div>
         </div>
       </div>