feat(ticket): record urges in thread, show urge count in admin, mail admins

- aksrt_ticket gains urge_count / last_urge_time (schema 3.1.0)
- cooldown moves from transient to an atomic conditional UPDATE
- urge inserts a system reply rendered as a centered notice (not quotable)
- admin list badge + info card row for urge count / last time
- new ticket_urge_admin mail event via aksrt_ticket_urged

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/Settings/MailTemplates.php

@@ -20,6 +20,7 @@ final class MailTemplates {
             'auth_apply_admin' => self::event('身份认证申请通知', '用户 {username} 提交了身份认证申请，请登录后台审核。\n查看地址：{url}', ['username', 'url']),
             'ban_appeal_admin' => self::event('账号申诉通知', '用户 {username} 提交了账号申诉。\n查看地址：{url}', ['username', 'url']),
             'report_admin' => self::event('举报提交通知', '收到新的举报。\n举报人：{username}\n对象：{title}\n查看地址：{url}', ['username', 'title', 'url']),
+            'ticket_urge_admin' => self::event('工单催单通知', '用户 {username} 催促处理工单（第 {count} 次）。\n工单：#{ticket_num} {title}\n查看地址：{url}', ['username', 'count', 'ticket_num', 'title', 'url']),
 
             'reg_verify_code' => self::event('注册验证码', '您好 {username}，\n\n您正在注册 {site_name}，验证码为：\n\n【{code}】\n\n验证码 10 分钟内有效。如非本人操作，请忽略此邮件。', ['username', 'site_name', 'code']),
             'reg_success' => self::event('注册成功', '您好 {username}，\n\n欢迎加入 {site_name}！您的账号已注册成功。\n\n登录地址：{url}', ['username', 'site_name', 'url']),
@@ -95,7 +96,7 @@ final class MailTemplates {
                 ['key' => 'mail_more_content', 'label' => '邮件附加内容（支持基础 HTML）', 'type' => 'textarea', 'rows' => 3, 'sanitize_type' => 'html', 'default' => $defaults['mail_more_content']],
             ]],
         ];
-        $admin = ['links_submit_admin', 'order_paid_admin', 'withdraw_submitted_admin', 'post_pending_admin', 'auth_apply_admin', 'ban_appeal_admin', 'report_admin'];
+        $admin = ['links_submit_admin', 'order_paid_admin', 'withdraw_submitted_admin', 'post_pending_admin', 'auth_apply_admin', 'ban_appeal_admin', 'report_admin', 'ticket_urge_admin'];
         $user = array_values(array_diff(array_keys($definitions), $admin));
         $groups[] = self::event_group('admin', '管理员邮件推送', $admin, $definitions, $defaults);
         $groups[] = self::event_group('user', '用户邮件推送', $user, $definitions, $defaults);