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>

assets/admin/src/pages/tools/ToolsBackup.vue

@@ -1,5 +1,5 @@
 <template>
-  <div class="aksrt-page-container">
+  <div class="jio-page-container">
     <PageHeader
       title="数据备份"
       desc="管理设置快照、创建手动备份，并执行恢复或删除。"
@@ -12,8 +12,8 @@
     </PageHeader>
 
     <n-spin :show="loading" style="width: 100%; min-height: 200px;">
-      <n-card class="aksrt-section-card">
-        <div class="aksrt-section-header">
+      <n-card class="jio-section-card">
+        <div class="jio-section-header">
           <h3>备份策略</h3>
         </div>
         <n-space vertical size="small" style="width: 100%;">
@@ -26,19 +26,19 @@
             <n-tag round :type="backups.length ? 'success' : 'default'">现有快照：{{ backups.length }} 份</n-tag>
           </n-space>
           <n-space align="center" wrap>
-            <span class="aksrt-backup__label">自动备份</span>
+            <span class="jio-backup__label">自动备份</span>
             <n-switch v-model:value="settings.backup_auto" />
-            <span class="aksrt-backup__label">频率</span>
+            <span class="jio-backup__label">频率</span>
             <n-select v-model:value="settings.backup_frequency" :options="frequencyOptions" style="width: 140px;" />
-            <span class="aksrt-backup__label">保留</span>
+            <span class="jio-backup__label">保留</span>
             <n-input-number v-model:value="settings.backup_retain" :min="3" :max="20" style="width: 140px;" />
             <n-button type="primary" :loading="savingPolicy" @click="handleSavePolicy">保存策略</n-button>
           </n-space>
         </n-space>
       </n-card>
 
-      <n-card class="aksrt-section-card">
-        <div class="aksrt-section-header">
+      <n-card class="jio-section-card">
+        <div class="jio-section-header">
           <h3>手动创建快照</h3>
         </div>
         <n-space vertical size="small" style="width: 100%;">
@@ -50,8 +50,8 @@
         </n-space>
       </n-card>
 
-      <n-card class="aksrt-section-card">
-        <div class="aksrt-section-header">
+      <n-card class="jio-section-card">
+        <div class="jio-section-header">
           <h3>快照列表</h3>
         </div>
         <n-empty v-if="!backups.length" description="暂无设置快照" />
@@ -64,7 +64,7 @@
           :single-line="false"
           :scroll-x="900"
         />
-        <p class="aksrt-backup__hint">
+        <p class="jio-backup__hint">
           恢复非当前网站 / 非当前版本的快照可能导致配置异常，恢复前请确认站点环境一致。
         </p>
       </n-card>
@@ -264,14 +264,14 @@ async function handleDelete(row) {
 </script>
 
 <style scoped>
-.aksrt-backup__hint {
+.jio-backup__hint {
   margin: 12px 0 0;
   color: #667085;
   font-size: 12px;
   line-height: 1.7;
 }
 
-.aksrt-backup__label {
+.jio-backup__label {
   color: #344054;
   font-size: 12px;
 }