fix(frontend): guard against non-array selectedFields in renderFieldTags

When config.fields is a non-array value (e.g. empty object {}),
the fallback logic could still result in a non-array if both
config.fields and config.selectedFields are abnormal values.
Added double-guard: after the fallback chain, explicitly assert
Array.isArray before using selectedFields.includes().

Fixes: TypeError: _.includes is not a function on rules/new page.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/components/rules/new/ReviewSettings.tsx

@@ -792,21 +792,22 @@ export function ReviewSettings({
 
   // 渲染字段标签，确保已选择的字段即使在新的字段列表中不存在也会显示
   const renderFieldTags = (ruleId: string, config: Record<string, unknown>) => {
-    // 获取规则的当前已选字段
-    // 修复：对于exists类型规则，应该使用fields而不是selectedFields
-    const selectedFields = Array.isArray(config.fields) ? 
-      config.fields as string[] : 
-      (Array.isArray(config.selectedFields) ? config.selectedFields as string[] : []);
-    
+    // 获取规则的当前已选字段（防御性：确保总是数组）
+    const rawSelected = Array.isArray(config.fields)
+      ? config.fields
+      : (Array.isArray(config.selectedFields) ? config.selectedFields : []);
+    const selectedFields: string[] = Array.isArray(rawSelected) ? rawSelected : [];
+
     // 优先使用配置中存储的可用字段，如果没有则使用当前可用字段
-    const fieldsToRender = Array.isArray(config.availableFields) ? 
-      config.availableFields as string[] : 
-      availableFields;
-    
+    const rawFieldsToRender = Array.isArray(config.availableFields)
+      ? config.availableFields
+      : availableFields;
+    const fieldsToRender: string[] = Array.isArray(rawFieldsToRender) ? rawFieldsToRender : [];
+
     return (
       <div className="field-tags">
         {fieldsToRender.map((field, index) => {
-          // 使用includes方法检查选中状态
+          // 使用includes方法检查选中状态（selectedFields 总是数组，不会抛错）
           const isSelected = selectedFields.includes(field);
           
           return (