fix(pdd): 兼容 EXTERNAL_PDD_SKU_OVERRIDES=[] 字符串绑定 List（K8s/Helm 环境变量）

Made-with: Cursor

service/src/main/java/cn/qihangerp/service/external/pdd/ExternalPddConfiguration.java

@@ -1,7 +1,16 @@
 package cn.qihangerp.service.external.pdd;
 
+import com.alibaba.fastjson2.JSON;
+import com.alibaba.fastjson2.JSONException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.convert.converter.Converter;
+
+import java.util.ArrayList;
+import java.util.List;
 
 /**
  * @author guochengyu
@@ -9,4 +18,28 @@ import org.springframework.context.annotation.Configuration;
 @Configuration
 @EnableConfigurationProperties(ExternalPddProperties.class)
 public class ExternalPddConfiguration {
+
+    private static final Logger log = LoggerFactory.getLogger(ExternalPddConfiguration.class);
+
+    /**
+     * K8s/Helm 常把 {@code sku-overrides: []} 落成环境变量 {@code EXTERNAL_PDD_SKU_OVERRIDES=[]}（字符串），
+     * 默认 Binder 无法转为 {@link List}；此处兼容 {@code []}、空串及 JSON 数组。
+     */
+    @Bean
+    public Converter<String, List<ExternalPddProperties.PddSkuOverride>> externalPddSkuOverridesStringConverter() {
+        return source -> {
+            String s = source == null ? "" : source.trim();
+            if (s.isEmpty() || "[]".equals(s)) {
+                return new ArrayList<>();
+            }
+            try {
+                List<ExternalPddProperties.PddSkuOverride> list =
+                        JSON.parseArray(s, ExternalPddProperties.PddSkuOverride.class);
+                return list != null ? list : new ArrayList<>();
+            } catch (JSONException e) {
+                log.warn("external.pdd.sku-overrides 环境变量/配置非合法 JSON，已按空列表处理: {}", e.getMessage());
+                return new ArrayList<>();
+            }
+        };
+    }
 }