- Point the 浏览器图标 / 移动端图标 schema defaults (PHP + VUE) at
assets/img/favicon.png instead of an empty media field.
- Fall back to the same PNG in Settings::favicon_url() when no custom
favicon and no native site_icon are configured.
- Add Settings::mobile_icon_url() and emit apple-touch-icon from SEOHead;
the 移动端图标 field previously had no consumer and never reached the page.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>