chore(branding): remove leftover upstream theme identifiers

The theme was renamed Zibll/子比 → AKSRT → Jio, but upstream branding
survived the sweeps in CSS classes, the SVG sprite prefix, a persisted
widget field ID, JS events, admin Vue class names, test infrastructure
and docblocks.

Renames:
- zib-widget / zib-widget-wrap / zib-slider → jio-widget-box /
  jio-widget-box-wrap / jio-slider-box (jio-widget is taken by the modern
  widget shell, jio-box-* by the card primitives)
- zib-partners-scroll + zps-* → jio-partners-scroll + jps-*
- zib-combo-info-card + zci-* → jio-combo-info-card + jci-*
- zibsvg- → jiosvg-, including the exported picker helpers and the
  fa-zibsvg- family-prefix guard
- zibpay_type → pay_type; the dual-read fallback in PostQuery collapses
  to a single key
- [zibajax="submit"] dropped (no PHP emitter); zib_ajax.success →
  jio_ajax.success
- aks-* admin Vue classes → jio-*
- zib_palette() → palette()

User-facing vendor traces are gone: the floating "more" button default no
longer ships a zibll.com link or 子比主题 marketing copy, the notice
widget ships no preset promo entries, and the four 官网教程 links are
removed from the post-list admin schema.

Test infrastructure renamed to neutral names (docker-compose.reference.yml,
Caddyfile, article-baseline.json, modern-widgets-contract.test.cjs) with
their DB/volume/env/slug identifiers following.

Kept intentionally, documented in tests/fixtures/README.md: the golden
fixture reference fingerprint (a SHA-256 record of an external directory,
read by validate-widget-golden / generate-widget-golden-fixture /
audit-widget-system), the doesNotMatch guards that prove the old tokens are
gone, and the reference theme's own meta key in the visual fixtures.

No backward-compat or data migration: saved widget configs holding old
icon keys or the old field ID silently lose them, per the project's
rewrite-over-compatibility rule.

Verified: 132/132 node contract tests, php tests/widget-system/run.php
(146 assertions), audit-admin-contracts, audit-psr4-paths and
validate-widget-golden all green; tracked bundles regenerated and in sync.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

tests/admin/baidu-push-settings-reference-contract.test.cjs

@@ -1,7 +1,7 @@
 'use strict';
 
 /**
- * 「百度推送」后台设置页契约（对齐参考主题 zibll）：
+ * 「百度推送」后台设置页契约：
  * 1) PHP schema（SchemaExtensionsPush.php）与 JS schema（push.js）字段键、顺序、默认值一致；
  * 2) 参考主题字段全集存在：自动推送 JS、普通收录、快速收录、准入 Token、发布/更新触发；
  * 3) 双路/迁移字段（SEO 页 seo_baidu_*、熊掌号 xzh_*、批量推送 batch_*）已彻底移除，无双路兼容；
@@ -27,7 +27,7 @@ const displayGroups = fs.readFileSync(path.join(root, 'src/Settings/DisplayPageG
 const metaBox = fs.readFileSync(path.join(root, 'src/Extensions/SearchPushMetaBox.php'), 'utf8');
 const functions = fs.readFileSync(path.join(root, 'functions.php'), 'utf8');
 
-// 参考主题（zibll）百度推送字段全集，Jio 单一 canonical 配置面（扩展&增强 → 百度推送）。
+// 百度推送字段全集，Jio 单一 canonical 配置面（扩展&增强 → 百度推送）。
 const REFERENCE_KEYS = [
   'baidu_push_enabled',
   'baidu_push_token',