fix(email): lock templates to built-in catalog

src/Settings/MailTemplates.php

@@ -70,8 +70,6 @@ final class MailTemplates {
         ];
         foreach ($definitions as $event => $definition) {
             $defaults["email_{$event}_enabled"] = (bool) $definition['enabled'];
-            $defaults["email_{$event}_subject"] = $definition['title'];
-            $defaults["email_{$event}_content"] = $definition['content'];
         }
         return $defaults;
     }
@@ -114,8 +112,6 @@ final class MailTemplates {
         foreach ($events as $event) {
             $definition = $definitions[$event];
             $fields[] = ['key' => "email_{$event}_enabled", 'label' => "{$definition['title']}：启用", 'type' => 'switch', 'default' => $defaults["email_{$event}_enabled"]];
-            $fields[] = ['key' => "email_{$event}_subject", 'label' => "{$definition['title']}：主题模板", 'type' => 'input', 'default' => $defaults["email_{$event}_subject"]];
-            $fields[] = ['key' => "email_{$event}_content", 'label' => "{$definition['title']}：正文模板", 'type' => 'textarea', 'rows' => 6, 'sanitize_type' => 'html', 'default' => $defaults["email_{$event}_content"], 'help' => '可用占位符：' . implode('、', array_map(static fn(string $p): string => '{' . $p . '}', $definition['placeholders']))];
         }
         return ['key' => $key, 'title' => $title, 'fields' => $fields];
     }