feat: persistent Zabbix-style sidebar on all pages, rename Dashboard to Обзор

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

frontend/src/App.vue

@@ -1,5 +1,18 @@
 <template>
-  <div class="layout">
-    <RouterView />
+  <div :class="showShell ? 'app-shell' : 'layout layout-login'">
+    <AppSidebar v-if="showShell" />
+    <main :class="showShell ? 'app-main' : ''">
+      <RouterView />
+    </main>
   </div>
 </template>
+
+<script setup lang="ts">
+import { computed } from "vue";
+import { useRoute } from "vue-router";
+import { getToken } from "./api";
+import AppSidebar from "./components/AppSidebar.vue";
+
+const route = useRoute();
+const showShell = computed(() => route.path !== "/login" && !!getToken());
+</script>