feat(preview): disable attachment previews when unavailable

Signed-off-by: Sebastian <krupinski01@gmail.com>

src/components/MessageReader.vue

@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import { computed, ref, watch } from 'vue'
-import { useUser } from '@KTXC'
+import { usePreviewStore, useUser } from '@KTXC'
 import { useMailUiStore } from '@/stores/mailUiStore'
 import type { EntityObject, MessageObject } from '@MailManager/models'
 import { SecurityLevel } from '@/utile/emailSanitizer'
@@ -29,6 +29,7 @@ const emit = defineEmits<{
 
 // User settings
 const { getSetting } = useUser()
+const previewStore = usePreviewStore()
 const mailUiStore = useMailUiStore()
 
 // Security overrides
@@ -65,6 +66,7 @@ const effectiveSecurityLevel = computed(() => {
 // Preview state
 const previewDialog = computed(() => mediaViewerComponent('dialog'))
 const previewItems = computed<MediaViewerItem[]>(() => {
+  if (!previewStore.availability.storage) return []
   const attachments = message.value?.attachments ?? []
   const items: MediaViewerItem[] = []
   attachments.forEach((attachment, index) => {