[ui] omit blobpreview if missing

webui/src/components/display/BlobPreview.svelte

@@ -6,9 +6,15 @@
   $: ({ entity } = useEntity(address));
 
   $: mimeType = String($entity?.get("FILE_MIME"));
+  $: handled =
+    Boolean(mimeType) &&
+    ["audio", "video", "image", "model"].some((prefix) =>
+      mimeType.startsWith(prefix)
+    );
 </script>
 
-<div class="preview" v-if="mimeType">
+{#if handled}
+  <div class="preview">
     {#if mimeType?.startsWith("audio")}
       <audio controls preload="auto" src="/api/raw/{address}" />
     {/if}
@@ -30,6 +36,7 @@
       <ModelViewer src="/api/raw/{address}" />
     {/if}
   </div>
+{/if}
 
 <style scoped lang="scss">
   .preview {