CDN 与源站：缓存键与回源字段 / CDN + origin cache-key notes

接 CDN 时建议写清：缓存键是否含查询串、哪些路径 bypass、源站防火墙是否放行 CDN IP、HTTPS 证书在边缘还是源站。配置因厂商而异；以官方文档为准。

English: Cache keys, bypass paths, allowlist CDN egress, cert termination — follow vendor docs.

CDN tip: document bypass paths for /wp-admin, APIs, and cart checkouts before enabling aggressive caching.