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/visual/docker-compose.reference.yml

@@ -0,0 +1,78 @@
+name: jio-visual-reference
+
+services:
+  db:
+    image: mariadb:11.4
+    environment:
+      MARIADB_DATABASE: reference
+      MARIADB_USER: visual
+      MARIADB_PASSWORD: visual
+      MARIADB_RANDOM_ROOT_PASSWORD: "1"
+    volumes:
+      - reference_db:/var/lib/mysql
+    healthcheck:
+      test: ["CMD", "healthcheck.sh", "--connect", "--innodb_initialized"]
+      interval: 5s
+      timeout: 5s
+      retries: 20
+
+  wordpress:
+    image: wordpress:php8.1-apache
+    depends_on:
+      db:
+        condition: service_healthy
+    environment:
+      WORDPRESS_DB_HOST: db
+      WORDPRESS_DB_USER: visual
+      WORDPRESS_DB_PASSWORD: visual
+      WORDPRESS_DB_NAME: reference
+    volumes:
+      - reference_wp:/var/www/html
+      - type: bind
+        source: ${REFERENCE_THEME_PATH}
+        target: /var/www/html/wp-content/themes/reference
+        read_only: true
+      - type: bind
+        source: .
+        target: /visual-fixtures
+        read_only: true
+
+  caddy:
+    image: caddy:2.8-alpine
+    depends_on:
+      - wordpress
+    ports:
+      - "9443:443"
+    volumes:
+      - ./Caddyfile:/etc/caddy/Caddyfile:ro
+      - reference_caddy_data:/data
+
+  wp:
+    image: wordpress:cli-php8.1
+    depends_on:
+      db:
+        condition: service_healthy
+      wordpress:
+        condition: service_started
+    user: "33:33"
+    environment:
+      WORDPRESS_DB_HOST: db
+      WORDPRESS_DB_USER: visual
+      WORDPRESS_DB_PASSWORD: visual
+      WORDPRESS_DB_NAME: reference
+    volumes:
+      - reference_wp:/var/www/html
+      - type: bind
+        source: ${REFERENCE_THEME_PATH}
+        target: /var/www/html/wp-content/themes/reference
+        read_only: true
+      - type: bind
+        source: .
+        target: /visual-fixtures
+        read_only: true
+    entrypoint: ["wp"]
+
+volumes:
+  reference_db:
+  reference_wp:
+  reference_caddy_data: