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>

inc/helpers/jio-icon-cards.php

@@ -11,7 +11,7 @@ if (!function_exists('jio_icon_card_kses_tags')) :
 	/**
 	 * Inline HTML allow-list for icon card title/desc fields.
 	 *
-	 * legacy (Zibll) stores and echoes card title/desc raw, so admin-authored
+	 * Card title/desc are stored and echoed raw, so admin-authored
 	 * markup such as `<badge class="ml6 jb-blue">GO <span class="fa ..."></span></badge>`
 	 * renders verbatim. `badge` is a custom element missing from WP's
 	 * `$allowedposttags`, so `wp_kses_post()` strips it; these fields must go
@@ -54,12 +54,12 @@ if (!function_exists('jio_card_icon_inner')) :
 	 *
 	 * The universal icon picker stores three formats:
 	 *  - "fa fas fa-star"   — FA5 class string
-	 *  - "zibsvg-hot"       — theme built-in SVG sprite key
+	 *  - "jiosvg-hot"       — theme built-in SVG sprite key
 	 *  - "customsvg-<svg>"  — inline custom SVG markup
 	 *
 	 * Every format must be routed through jio_icon_markup(); emitting a bare
 	 * FA class string silently produced an empty glyph for the two SVG formats
-	 * (e.g. `<i class="fa fas fa-zibsvg-hot">`), so the card rendered without an
+	 * (e.g. `<i class="fa fas fa-jiosvg-hot">`), so the card rendered without an
 	 * icon whenever the admin picked 内置 SVG or 自定义 SVG.
 	 *
 	 * Raw inline markup without a picker prefix is still accepted for data
@@ -75,7 +75,7 @@ if (!function_exists('jio_card_icon_inner')) :
 			return '';
 		}
 
-		$is_picker_svg = str_starts_with($value, 'zibsvg-') || str_starts_with($value, 'customsvg-');
+		$is_picker_svg = str_starts_with($value, 'jiosvg-') || str_starts_with($value, 'customsvg-');
 
 		if (!$is_picker_svg && str_contains($value, '<')) {
 			$allowed = function_exists('jio_svg_kses_tags') ? jio_svg_kses_tags() : [];
@@ -270,7 +270,7 @@ if (!function_exists('jio_icon_cover_card')) :
 			$custom_src  = (string) ($args['custom_icon'] !== '' ? $args['custom_icon'] : $args['customize_icon']);
 			$icon_img    = esc_url_raw(trim((string) ($args['icon_image'] !== '' ? $args['icon_image'] : '')));
 			$custom_html = '';
-			$custom_is_picker = str_starts_with($custom_src, 'zibsvg-') || str_starts_with($custom_src, 'customsvg-');
+			$custom_is_picker = str_starts_with($custom_src, 'jiosvg-') || str_starts_with($custom_src, 'customsvg-');
 			if ($icon_img === '' && $custom_is_picker) {
 				// A picker value routed into the custom slot must go through the
 				// shared renderer, otherwise the "customsvg-" prefix leaks as text.