refactor: rename the theme brand and every identifier from AKSRT to Jio

Full-project rename. `git grep -i aksrt` is now empty apart from the
DBMigrator 3.3.0 changelog note that documents the rename itself.

Code identifiers
- PHP namespace AKSRT\ -> Jio\ (composer PSR-4 + 378 declarations)
- global constants AKSRT_* -> JIO_* (VERSION/DIR/URI, PAY_TYPE_*, CAPTCHA_*)
- procedural functions, hooks, options, meta keys, table names,
  cookies, query vars, ajax actions and nonces: aksrt_ -> jio_
- text domain aksrt -> jio; Theme Name -> Jio
- JS globals: aksrtData/aksrtAdminData/... -> jioData/jioAdminData/...,
  window.AKSRTCaptcha & friends -> window.JioCaptcha, Aksrt* -> Jio*
- Vue components Aks*.vue -> Jio*.vue (15 files renamed + imports)
- CSS classes/data-attrs/custom properties: aksrt- -> jio-
- REST namespace aksrt/v1 -> jio/v1 (incl. payment gateway callbacks)

Storage layer
- DB tables {prefix}aksrt_* -> {prefix}jio_*; SCHEMA_VERSION 3.2.0 -> 3.3.0
  so dbDelta creates the new names on install
- widget id_base aksrt_widget_* -> jio_widget_*
- uninstall.php drop list rebuilt from the actual migrator tables
  (dropped 3 stale entries, added the 17 missing ones)

Removed
- hardcoded https://api.aksrt.com/version.json default update endpoint;
  get_endpoint() now reads the 「更新端点」 setting and do_check() no-ops
  when it is empty

Files renamed: inc/helpers/aksrt-*.php -> jio-*.php (54),
assets/admin/src/components/form/Aks*.vue -> Jio*.vue (15).
Build artifacts regenerated: assets/css/build, assets/js/runtime,
assets/admin/build.

Verified: audit-psr4-paths errors=0, audit-admin-contracts errors=0
(warnings=56, unchanged baseline), 813/813 widget-system tests,
44/44 phpunit, php -l clean across all PHP.

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

tests/fixtures/page-visual-matrix-v1.json

@@ -1,5 +1,5 @@
 {
-  "schema": "aksrt.page-visual-matrix.v1",
+  "schema": "jio.page-visual-matrix.v1",
   "reference": "https://localhost:9443",
   "candidate": "https://localhost",
   "viewports": {
@@ -12,11 +12,11 @@
   "routes": [
     {"id": "home", "path": "/", "states": ["default", "hover", "loading", "error"]},
     {"id": "archive", "path": "/?post_type=post", "states": ["default", "numbered", "load-more", "infinite"]},
-    {"id": "category", "path": "/category/aksrt_zibll_v1_101/", "states": ["default", "empty"]},
-    {"id": "tag", "path": "/tag/aksrt_zibll_v1_103/", "states": ["default", "empty"]},
-    {"id": "search", "path": "/?s=AKSRT", "states": ["default", "empty", "focus"]},
-    {"id": "single", "path": "/aksrt_zibll_v1_301/", "states": ["default", "hover", "toc-open"]},
-    {"id": "resource", "path": "/aksrt_zibll_v1_303/", "states": ["locked", "authorized", "download"]},
+    {"id": "category", "path": "/category/jio_zibll_v1_101/", "states": ["default", "empty"]},
+    {"id": "tag", "path": "/tag/jio_zibll_v1_103/", "states": ["default", "empty"]},
+    {"id": "search", "path": "/?s=Jio", "states": ["default", "empty", "focus"]},
+    {"id": "single", "path": "/jio_zibll_v1_301/", "states": ["default", "hover", "toc-open"]},
+    {"id": "resource", "path": "/jio_zibll_v1_303/", "states": ["locked", "authorized", "download"]},
     {"id": "page", "path": "/sample-page/", "states": ["default"]},
     {"id": "login", "path": "/wp-login.php", "states": ["default", "focus", "error"]},
     {"id": "user", "path": "/user/", "states": ["guest", "member", "vip"]},