fix: avoid TaskTree navigation icon crash

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/hwlab-cloud-web/src/components/layout/AppNavigation.vue

@@ -13,7 +13,6 @@ import {
   Cpu,
   CreditCard,
   FolderKanban,
-  GanttChart,
   Gauge,
   KeyRound,
   LayoutDashboard,
@@ -114,7 +113,7 @@ const navSections = [
         name: "TaskTree",
         label: "TaskTree",
         path: "/projects/tasktree",
-        icon: GanttChart,
+        icon: ChartBar,
         navId: "project.tasktree",
       },
     ],