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>

src/Core/FrontSubmitMedia.php

@@ -1,11 +1,11 @@
 <?php
 /**
- * @package AKSRT
+ * @package Jio
  */
 
-namespace AKSRT\Core;
+namespace Jio\Core;
 
-use AKSRT\Attachment\PendingUploads;
+use Jio\Attachment\PendingUploads;
 
 defined('ABSPATH') || exit;
 
@@ -195,8 +195,8 @@ trait FrontSubmitMedia {
 			}
 		}
 
-		$pay_meta = function_exists('aksrt_get_pay_meta')
-			? aksrt_get_pay_meta($post_id)
+		$pay_meta = function_exists('jio_get_pay_meta')
+			? jio_get_pay_meta($post_id)
 			: get_post_meta($post_id, DomainModel::PAY_META_KEY, true);
 		$pay_meta = is_array($pay_meta) ? $pay_meta : [];
 		$download_urls = [];
@@ -239,18 +239,18 @@ trait FrontSubmitMedia {
 			'posts_per_page' => -1,
 			'fields'         => 'ids',
 			'no_found_rows'  => true,
-			'meta_key'       => '_aksrt_front_submit_media',
+			'meta_key'       => '_jio_front_submit_media',
 		]);
 		foreach (array_map('absint', $existing) as $attachment_id) {
 			if (!isset($desired[$attachment_id])) {
 				$wpdb->update($wpdb->posts, ['post_parent' => 0], ['ID' => $attachment_id], ['%d'], ['%d']);
 				clean_post_cache($attachment_id);
-				delete_post_meta($attachment_id, '_aksrt_front_submit_media');
+				delete_post_meta($attachment_id, '_jio_front_submit_media');
 			}
 		}
 		foreach ($desired as $attachment_id => $kind) {
 			$attachment_id = (int) $attachment_id;
-			update_post_meta($attachment_id, '_aksrt_front_submit_media', $kind);
+			update_post_meta($attachment_id, '_jio_front_submit_media', $kind);
 			$wpdb->update($wpdb->posts, ['post_parent' => $post_id], ['ID' => $attachment_id], ['%d'], ['%d']);
 			clean_post_cache($attachment_id);
 		}
@@ -267,7 +267,7 @@ trait FrontSubmitMedia {
 	private function extract_attachment_ids(string $content, string $type): array {
 		$ids = [];
 		if ($type === 'file') {
-			preg_match_all('/data-aksrt-file-id\s*=\s*["\']([^"\']+)["\']/i', $content, $matches);
+			preg_match_all('/data-jio-file-id\s*=\s*["\']([^"\']+)["\']/i', $content, $matches);
 		} elseif ($type === 'image') {
 			preg_match_all('/<img\b[^>]*data-edit-file-id\s*=\s*["\']([^"\']+)["\'][^>]*>/i', $content, $matches);
 		} else {