增加状态更新接口客户的状态可以是线索高一项第1项客户

src/main/java/com/rj/dto/CustomerStageUpdateResult.java

@@ -0,0 +1,35 @@
+package com.rj.dto;
+
+import com.rj.entity.CustomerManagement;
+import lombok.Getter;
+
+/**
+ * 客户阶段（stage）更新结果，供控制层映射 HTTP 状态与 JSON。
+ */
+@Getter
+public class CustomerStageUpdateResult {
+
+    private final int httpStatus;
+    private final boolean success;
+    private final String message;
+    private final CustomerManagement customer;
+
+    private CustomerStageUpdateResult(int httpStatus, boolean success, String message, CustomerManagement customer) {
+        this.httpStatus = httpStatus;
+        this.success = success;
+        this.message = message;
+        this.customer = customer;
+    }
+
+    public static CustomerStageUpdateResult ok(CustomerManagement customer) {
+        return new CustomerStageUpdateResult(200, true, "阶段更新成功", customer);
+    }
+
+    public static CustomerStageUpdateResult badRequest(String message) {
+        return new CustomerStageUpdateResult(400, false, message, null);
+    }
+
+    public static CustomerStageUpdateResult serverError(String message) {
+        return new CustomerStageUpdateResult(500, false, message, null);
+    }
+}