feat(tickets): make ticket title/content/reply length limits configurable

Add ticket_title_max / ticket_content_max / ticket_reply_max to the
users/ticket schema (PHP + SPA) with clamped TicketSettings readers.
All write paths (front REST, admin REST, note REST, native admin page)
and front-end maxlength/counters now read the configured limits.
Remove the hardcoded TICKET_CONTENT_MAX constant.

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

src/Admin/Native/UsersMenusTicketsList.php

@@ -45,8 +45,9 @@ trait UsersMenusTicketsList {
         }
         echo '</select></label>';
         printf(
-            '<label class="is-wide"><span>%s</span><input type="text" name="title" maxlength="200" required class="large-text" /></label>',
-            esc_html__('标题', 'aksrt')
+            '<label class="is-wide"><span>%s</span><input type="text" name="title" maxlength="%d" required class="large-text" /></label>',
+            esc_html__('标题', 'aksrt'),
+            \AKSRT\Ticket\TicketSettings::title_max()
         );
         if (\AKSRT\Ticket\TicketSettings::order_link_enabled()) {
             printf(
@@ -58,7 +59,7 @@ trait UsersMenusTicketsList {
         printf(
             '<label class="is-wide"><span>%s</span><textarea name="content" rows="4" maxlength="%d" required class="large-text"></textarea></label>',
             esc_html__('问题描述', 'aksrt'),
-            (int) self::TICKET_CONTENT_MAX
+            \AKSRT\Ticket\TicketSettings::content_max()
         );
         echo '</div>';
         printf(