chore(spec): 归档 blog-5n——八任务收敛（后台深度优化全家桶）

Spec: 2026-11-05_blog-5n-admin-deep-optimization

Co-authored-by: GLM-5.3

.spec/specs/archive/2026-11-05_blog-5n-admin-deep-optimization/evidence/verify_t7.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+set -euo pipefail
+cd "$(git rev-parse --show-toplevel)"
+node --check public/admin/preview-style.js
+grep -q "prefers-color-scheme: dark" public/admin/preview-style.js
+python3 -c "import json;m=json.load(open('public/admin/manifest.webmanifest'));assert m['start_url']=='/admin/' and len(m['icons'])==2"
+echo "verify_t7 OK"