[backport core/1.35] Fix buttons displayed behind images in litegraph (#7684)

Backport of #7627 to `core/1.35`

Automatically created by backport workflow.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7684-backport-core-1-35-Fix-buttons-displayed-behind-images-in-litegraph-2cf6d73d365081e28cdfc4b09d20cbba)
by [Unito](https://www.unito.io)

Co-authored-by: AustinMroz <austin@comfy.org>
Co-authored-by: github-actions <github-actions@github.com>

src/renderer/extensions/vueNodes/widgets/composables/useImagePreviewWidget.ts

@@ -265,14 +265,19 @@ const renderPreview = (
       }
     }
 
-    ctx.fillStyle = fill
-    ctx.beginPath()
-    ctx.roundRect(x, y, sz, sz, [4])
-    ctx.fill()
-    ctx.fillStyle = textFill
-    ctx.font = '12px Inter, sans-serif'
-    ctx.textAlign = 'center'
-    ctx.fillText(text, x + 15, y + 20)
+    deferredImageRenders.push(() => {
+      ctx.save()
+      ctx.setTransform(transform)
+      ctx.fillStyle = fill
+      ctx.beginPath()
+      ctx.roundRect(x, y, sz, sz, [4])
+      ctx.fill()
+      ctx.fillStyle = textFill
+      ctx.font = '12px Inter, sans-serif'
+      ctx.textAlign = 'center'
+      ctx.fillText(text, x + 15, y + 20)
+      ctx.restore()
+    })
 
     return isClicking
   }