fix(frontend): admin custom menu items not showing in sidebar

The public settings API filters out menu items with visibility='admin',
so customMenuItemsForAdmin was always empty when reading from
cachedPublicSettings. Fix by loading custom menu items from the admin
settings API (via adminSettingsStore) which returns all items unfiltered.

Changes:
- adminSettings store: store custom_menu_items from admin settings API
- AppSidebar: read admin menu items from adminSettingsStore instead of
  cachedPublicSettings
- CustomPageView: merge public and admin menu items so admin users can
  access admin-only custom pages

frontend/src/components/layout/AppSidebar.vue

@@ -579,7 +579,7 @@ const customMenuItemsForUser = computed(() => {
 })
 
 const customMenuItemsForAdmin = computed(() => {
-  const items = appStore.cachedPublicSettings?.custom_menu_items ?? []
+  const items = adminSettingsStore.customMenuItems ?? []
   return items
     .filter((item) => item.visibility === 'admin')
     .sort((a, b) => a.sort_order - b.sort_order)

frontend/src/stores/adminSettings.ts

 import { defineStore } from 'pinia'
 import { ref } from 'vue'
 import { adminAPI } from '@/api'
+import type { CustomMenuItem } from '@/types'
 
 export const useAdminSettingsStore = defineStore('adminSettings', () => {
   const loaded = ref(false)
@@ -43,6 +44,9 @@ export const useAdminSettingsStore = defineStore('adminSettings', () => {
     }
   }
 
+  // Custom menu items (all items including admin-only, loaded from admin settings API)
+  const customMenuItems = ref<CustomMenuItem[]>([])
+
   // Default open, but honor cached value to reduce UI flicker on first paint.
   const opsMonitoringEnabled = ref(readCachedBool('ops_monitoring_enabled_cached', true))
   const opsRealtimeMonitoringEnabled = ref(readCachedBool('ops_realtime_monitoring_enabled_cached', true))
@@ -64,6 +68,8 @@ export const useAdminSettingsStore = defineStore('adminSettings', () => {
       opsQueryModeDefault.value = settings.ops_query_mode_default || 'auto'
       writeCachedString('ops_query_mode_default_cached', opsQueryModeDefault.value)
 
+      customMenuItems.value = settings.custom_menu_items ?? []
+
       loaded.value = true
     } catch (err) {
       // Keep cached/default value: do not "flip" the UI based on a transient fetch failure.
@@ -122,6 +128,7 @@ export const useAdminSettingsStore = defineStore('adminSettings', () => {
     opsMonitoringEnabled,
     opsRealtimeMonitoringEnabled,
     opsQueryModeDefault,
+    customMenuItems,
     fetch,
     setOpsMonitoringEnabledLocal,
     setOpsRealtimeMonitoringEnabledLocal,

frontend/src/views/user/CustomPageView.vue

@@ -70,6 +70,7 @@ import { useRoute } from 'vue-router'
 import { useI18n } from 'vue-i18n'
 import { useAppStore } from '@/stores'
 import { useAuthStore } from '@/stores/auth'
+import { useAdminSettingsStore } from '@/stores/adminSettings'
 import AppLayout from '@/components/layout/AppLayout.vue'
 import Icon from '@/components/icons/Icon.vue'
 import { buildEmbeddedUrl, detectTheme } from '@/utils/embedded-url'
@@ -78,6 +79,7 @@ const { t } = useI18n()
 const route = useRoute()
 const appStore = useAppStore()
 const authStore = useAuthStore()
+const adminSettingsStore = useAdminSettingsStore()
 
 const loading = ref(false)
 const pageTheme = ref<'light' | 'dark'>('light')
@@ -86,8 +88,15 @@ let themeObserver: MutationObserver | null = null
 const menuItemId = computed(() => route.params.id as string)
 
 const menuItem = computed(() => {
-  const items = appStore.cachedPublicSettings?.custom_menu_items ?? []
-  const found = items.find((item) => item.id === menuItemId.value) ?? null
+  const publicItems = appStore.cachedPublicSettings?.custom_menu_items ?? []
+  const adminItems = authStore.isAdmin ? (adminSettingsStore.customMenuItems ?? []) : []
+  const allItems = [...publicItems]
+  for (const item of adminItems) {
+    if (!allItems.some((existing) => existing.id === item.id)) {
+      allItems.push(item)
+    }
+  }
+  const found = allItems.find((item) => item.id === menuItemId.value) ?? null
   if (found && found.visibility === 'admin' && !authStore.isAdmin) {
     return null
   }
@@ -122,12 +131,20 @@ onMounted(async () => {
     })
   }
 
-  if (appStore.publicSettingsLoaded) return
-  loading.value = true
-  try {
-    await appStore.fetchPublicSettings()
-  } finally {
-    loading.value = false
+  const promises: Promise<unknown>[] = []
+  if (!appStore.publicSettingsLoaded) {
+    promises.push(appStore.fetchPublicSettings())
+  }
+  if (authStore.isAdmin) {
+    promises.push(adminSettingsStore.fetch())
+  }
+  if (promises.length > 0) {
+    loading.value = true
+    try {
+      await Promise.all(promises)
+    } finally {
+      loading.value = false
+    }
   }
 })