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/widget-system/user-card-checkin-badge-contract.test.cjs

@@ -50,9 +50,9 @@ test('the badge typography is pinned to the reference bootstrap body values', ()
   const block = main.slice(start, main.indexOf('}', start))
   assert.match(block, /line-height:\s*1\.42857143/)
   // Reference body font stack (zibll bootstrap.min.css; zibll main.css does not
-  // override it), while AKSRT's reset imposes the modern --font-body stack.
+  // override it), while Jio's reset imposes the modern --font-body stack.
   assert.match(block, /font-family:\s*"Helvetica Neue", Helvetica, Arial, sans-serif/)
-  // The AKSRT html reset forces antialiased + optimizeLegibility; the badge
+  // The Jio html reset forces antialiased + optimizeLegibility; the badge
   // restores the browser defaults the reference renders with.
   assert.match(block, /-webkit-font-smoothing:\s*auto/)
   assert.match(block, /text-rendering:\s*auto/)
@@ -81,16 +81,16 @@ test('the sidebar widget link color does not recolor the check-in badge', () =>
 })
 
 test('the user-card check-in badge renders without the dead is-done class and bare span', () => {
-  const userbox = read('inc/helpers/aksrt-header-userbox.php')
-  const fnStart = userbox.indexOf('function aksrt_header_user_checkin_btn')
-  assert.notEqual(fnStart, -1, 'missing aksrt_header_user_checkin_btn')
+  const userbox = read('inc/helpers/jio-header-userbox.php')
+  const fnStart = userbox.indexOf('function jio_header_user_checkin_btn')
+  assert.notEqual(fnStart, -1, 'missing jio_header_user_checkin_btn')
   const fnEnd = userbox.indexOf('if (!function_exists', fnStart)
   assert.notEqual(fnEnd, -1)
   const fn = userbox.slice(fnStart, fnEnd)
 
   // Signed card badge: the badge class passes through untouched and the done
   // label is bare text after the icon, matching the reference markup.
-  assert.match(fn, /aksrt_get_user_checkin_details_link\(\s*\$class,/)
+  assert.match(fn, /jio_get_user_checkin_details_link\(\s*\$class,/)
   assert.doesNotMatch(fn, /\$class \. ' is-done'/)
   assert.doesNotMatch(fn, /'<span>'/)