fix: add missing system-audit search key to sidebar template

The backend returns system-audit results but the sidebar had no
matching <li data-search-key="system-audit"> element, causing a
console warning on every global search query.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

templates/partials/app-main-aside.phtml

@@ -605,6 +605,17 @@ $csrfToken = (string) ($layoutNav['csrfToken'] ?? '');
                             <ul class="app-search-preview" data-search-preview></ul>
                         </li>
                     <?php endif; ?>
+                    <?php if ($canViewSystemAudit): ?>
+                        <?php $systemAuditSearch = navActive('admin/system-audit', true); ?>
+                        <li data-search-key="system-audit" data-search-base="<?php e(lurl('admin/system-audit')); ?>">
+                            <a href="<?php e(lurl('admin/system-audit')); ?>" class="<?php e($systemAuditSearch['class']); ?>"
+                                <?php echo $systemAuditSearch['aria']; ?>>
+                                <span><?php e(t('System audit')); ?></span>
+                                <span class="badge" data-search-count>0</span>
+                            </a>
+                            <ul class="app-search-preview" data-search-preview></ul>
+                        </li>
+                    <?php endif; ?>
                 </ul>
             </nav>
         </div>