feat(viewer,ui04): E02 static fidelity — real photo fixtures, measured shell/photo/collapse specs, edge fade

- fixtures: 8 picsum-seeded real photos (mixed ratios); seedPhoto thumbBytes/browseBytes injection
- e2e E02 block: wrapper shell (195x280/radius/border/#10161E), photo strip (193w, ratio-height, 3px gap), collapse (44/44 hit, 24 visual, sole button), desktop+mobile screenshots
- EmbedStream: top/bottom 12px dark fade (0.12, §2.3 optional item)
- fix(admin): pre-existing eslint globals gap for ElNotification (template drift, blocks lint gate)

Co-Authored-By: Claude Code <noreply@anthropic.com>

apps/admin/src/utils/system/embedSlots.spec.ts

@@ -229,7 +229,9 @@ describe('嵌入代码 data-* 显式覆盖（UI-01：仅非默认字段，缺省
 
 describe('嵌入代码 v2 入口（UI-04：displayMode=vertical-stream → /embed/v2/）', () => {
   it('v2 默认 settings → 裸 v2 引用（无 v1 布局 data-*）', () => {
-    expect(buildEmbedSnippet('https://view.example.com', 'tok', { ...DEFAULT_EMBED_SETTINGS })).toBe(
+    expect(
+      buildEmbedSnippet('https://view.example.com', 'tok', { ...DEFAULT_EMBED_SETTINGS })
+    ).toBe(
       '<script src="https://view.example.com/embed/v2/loader.js" data-slot="tok" defer></script>'
     )
   })