feat(mindspace): add SEO/GEO delivery, page template catalog, and admin hooks

Enable optional SEO/GEO injection and discovery routes for confirmed public pages while keeping private pages noindex. Add premium page template skills, portal catalog API, template shop UI, and Baidu push gated by memind_adm config.

Co-authored-by: Cursor <cursoragent@cursor.com>

public/assets/template-previews/survey-basic.svg

@@ -0,0 +1,14 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="640" height="360" viewBox="0 0 640 360" role="img" aria-label="问卷 Page Data 模板预览">
+  <rect width="640" height="360" fill="#f5f0e5"/>
+  <rect x="120" y="28" width="400" height="304" rx="24" fill="#ffffff" filter="drop-shadow(0 16px 40px rgba(45,53,47,0.12))"/>
+  <text x="152" y="76" fill="#18211d" font-family="system-ui,sans-serif" font-size="26" font-weight="800">活动报名</text>
+  <text x="152" y="104" fill="#5c655f" font-family="system-ui,sans-serif" font-size="13">Page Data 问卷壳 · 前台提交</text>
+  <rect x="152" y="124" width="336" height="36" rx="12" fill="#faf8f3" stroke="#d7d0c1"/>
+  <rect x="152" y="176" width="336" height="36" rx="12" fill="#faf8f3" stroke="#d7d0c1"/>
+  <rect x="152" y="228" width="336" height="36" rx="12" fill="#faf8f3" stroke="#d7d0c1"/>
+  <text x="164" y="147" fill="#8a938d" font-family="system-ui,sans-serif" font-size="12">姓名</text>
+  <text x="164" y="199" fill="#8a938d" font-family="system-ui,sans-serif" font-size="12">手机号</text>
+  <text x="164" y="251" fill="#8a938d" font-family="system-ui,sans-serif" font-size="12">参与人数</text>
+  <rect x="152" y="284" width="336" height="36" rx="18" fill="#2f6f57"/>
+  <text x="292" y="308" fill="#ffffff" font-family="system-ui,sans-serif" font-size="14" font-weight="700" text-anchor="middle">提交报名</text>
+</svg>