feat: add Storybook stories for Display components (#9702)

## Summary
- Add Storybook stories for `WidgetImageCompare` (Default,
WithBatchNavigation, SingleImageFallback, NoImages)
- WidgetGalleria and ImagePreview stories are deferred pending PrimeVue
removal

## Test plan
- [x] `pnpm typecheck` passes
- [x] `pnpm lint` passes
- [x] Verified all stories render correctly in Storybook

Figma ref:
https://www.figma.com/design/vALUV83vIdBzEsTJAhQgXq/Comfy-Design-System?node-id=55-1536

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9702-feat-add-Storybook-stories-for-Display-components-31f6d73d365081e781faf3a8735aa3dc)
by [Unito](https://www.unito.io)

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

src/renderer/extensions/vueNodes/widgets/components/WidgetImageCompare.stories.ts

@@ -0,0 +1,104 @@
+import type { Meta, StoryObj } from '@storybook/vue3-vite'
+import { ref } from 'vue'
+
+import type { SimplifiedWidget } from '@/types/simplifiedWidget'
+
+import type { ImageCompareValue } from './WidgetImageCompare.vue'
+import WidgetImageCompare from './WidgetImageCompare.vue'
+
+function createSampleImage(label: string, fill: string): string {
+  const svg =
+    `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">` +
+    `<rect width="512" height="512" fill="${fill}" />` +
+    `<text x="50%" y="50%" fill="white" font-size="40"` +
+    ` text-anchor="middle" dominant-baseline="middle">` +
+    `${label}</text></svg>`
+  return `data:image/svg+xml;charset=utf-8,${encodeURIComponent(svg)}`
+}
+
+const SAMPLE_BEFORE = createSampleImage('Before', '#475569')
+const SAMPLE_AFTER = createSampleImage('After', '#0f766e')
+
+const meta: Meta<typeof WidgetImageCompare> = {
+  title: 'Components/Display/ImageCompare',
+  component: WidgetImageCompare,
+  tags: ['autodocs'],
+  parameters: { layout: 'centered' },
+  decorators: [
+    (story) => ({
+      components: { story },
+      template: '<div class="w-88 h-80"><story /></div>'
+    })
+  ]
+}
+
+export default meta
+type Story = StoryObj<typeof meta>
+
+export const Default: Story = {
+  render: () => ({
+    components: { WidgetImageCompare },
+    setup() {
+      const widget = ref<SimplifiedWidget<ImageCompareValue>>({
+        name: 'compare',
+        type: 'IMAGE_COMPARE',
+        value: {
+          beforeImages: [SAMPLE_BEFORE],
+          afterImages: [SAMPLE_AFTER]
+        }
+      })
+      return { widget }
+    },
+    template: '<WidgetImageCompare :widget="widget" />'
+  })
+}
+
+export const WithBatchNavigation: Story = {
+  render: () => ({
+    components: { WidgetImageCompare },
+    setup() {
+      const widget = ref<SimplifiedWidget<ImageCompareValue>>({
+        name: 'compare',
+        type: 'IMAGE_COMPARE',
+        value: {
+          beforeImages: [SAMPLE_BEFORE, SAMPLE_AFTER],
+          afterImages: [SAMPLE_AFTER, SAMPLE_BEFORE],
+          beforeAlt: 'Before batch',
+          afterAlt: 'After batch'
+        }
+      })
+      return { widget }
+    },
+    template: '<WidgetImageCompare :widget="widget" />'
+  })
+}
+
+export const SingleImageFallback: Story = {
+  render: () => ({
+    components: { WidgetImageCompare },
+    setup() {
+      const widget = ref<SimplifiedWidget<string>>({
+        name: 'compare',
+        type: 'IMAGE_COMPARE',
+        value: SAMPLE_BEFORE
+      })
+      return { widget }
+    },
+    template: '<WidgetImageCompare :widget="widget" />'
+  })
+}
+
+export const NoImages: Story = {
+  render: () => ({
+    components: { WidgetImageCompare },
+    setup() {
+      const widget = ref<SimplifiedWidget<ImageCompareValue>>({
+        name: 'compare',
+        type: 'IMAGE_COMPARE',
+        value: {}
+      })
+      return { widget }
+    },
+    template: '<WidgetImageCompare :widget="widget" />'
+  })
+}

src/renderer/extensions/vueNodes/widgets/components/WidgetImageCompare.test.ts

@@ -58,7 +58,7 @@ describe('WidgetImageCompare Display', () => {
       expect(images[1].attributes('src')).toBe('https://example.com/before.jpg')
 
       images.forEach((img) => {
-        expect(img.classes()).toContain('object-contain')
+        expect(img.classes()).toContain('object-cover')
       })
     })
   })
@@ -290,7 +290,6 @@ describe('WidgetImageCompare Display', () => {
 
       const slider = wrapper.find('[role="presentation"]')
       expect(slider.exists()).toBe(true)
-      expect(slider.classes()).toContain('bg-white')
     })
 
     it('does not render slider when no images', () => {

src/renderer/extensions/vueNodes/widgets/components/WidgetImageCompare.vue

@@ -26,14 +26,14 @@
     <div
       v-if="beforeImage || afterImage"
       ref="containerRef"
-      class="relative min-h-0 flex-1"
+      class="relative min-h-0 flex-1 overflow-hidden rounded-lg bg-node-component-surface py-4"
     >
       <img
         v-if="afterImage"
         :src="afterImage"
         :alt="afterAlt"
         draggable="false"
-        class="size-full object-contain"
+        class="absolute inset-0 size-full object-cover"
       />
 
       <img
@@ -41,12 +41,18 @@
         :src="beforeImage"
         :alt="beforeAlt"
         draggable="false"
-        class="absolute inset-0 size-full object-contain"
+        class="absolute inset-0 size-full object-cover"
-        :style="{ clipPath: `inset(0 ${100 - sliderPosition}% 0 0)` }"
+        :style="
+          hasCompareImages
+            ? { clipPath: `inset(0 ${100 - sliderPosition}% 0 0)` }
+            : undefined
+        "
       />
 
+      <!-- Circular drag handle -->
       <div
-        class="pointer-events-none absolute inset-y-0 z-10 w-0.5 bg-white shadow-md"
+        v-if="hasCompareImages"
+        class="pointer-events-none absolute top-1/2 z-10 size-6 -translate-1/2 rounded-full border-2 border-white bg-white/30 shadow-lg backdrop-blur-sm"
         :style="{ left: `${sliderPosition}%` }"
         role="presentation"
       />
@@ -142,6 +148,10 @@ const afterImage = computed(() => {
   return value?.afterImages?.[afterIndex.value] ?? ''
 })
 
+const hasCompareImages = computed(() =>
+  Boolean(beforeImage.value && afterImage.value)
+)
+
 const beforeAlt = computed(() => {
   const value = props.widget.value
   return !isSingleImage(value) && value?.beforeAlt