fix: tolerate numeric recharge timestamps

internal/integration/java.go

@@ -211,8 +211,8 @@ type UserTotalRecharge struct {
 	UserID     Int64Value    `json:"userId"`
 	Type       string        `json:"type"`
 	Amount     DecimalString `json:"amount"`
-	CreateTime string        `json:"createTime"`
+	CreateTime StringValue   `json:"createTime"`
-	UpdateTime string        `json:"updateTime"`
+	UpdateTime StringValue   `json:"updateTime"`
 }
 
 type FreightSellerPage struct {
@@ -343,6 +343,26 @@ func (v *DecimalString) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
+type StringValue string
+
+func (v *StringValue) UnmarshalJSON(data []byte) error {
+	raw := strings.TrimSpace(string(data))
+	if raw == "" || raw == "null" {
+		*v = ""
+		return nil
+	}
+	if strings.HasPrefix(raw, "\"") && strings.HasSuffix(raw, "\"") {
+		var parsed string
+		if err := json.Unmarshal(data, &parsed); err != nil {
+			return err
+		}
+		*v = StringValue(parsed)
+		return nil
+	}
+	*v = StringValue(raw)
+	return nil
+}
+
 func New(cfg config.Config) *Client {
 	return &Client{
 		cfg: cfg,

internal/integration/java_test.go

@@ -0,0 +1,31 @@
+package integration
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+func TestUserTotalRechargeAcceptsNumericTimestamps(t *testing.T) {
+	var item UserTotalRecharge
+	raw := []byte(`{
+		"id":"2049097310624870401",
+		"userId":"2042274349343506434",
+		"type":"SHIPPING_AGENT",
+		"amount":1.60,
+		"createTime":1777377844000,
+		"updateTime":1777556451000
+	}`)
+
+	if err := json.Unmarshal(raw, &item); err != nil {
+		t.Fatalf("json.Unmarshal() error = %v", err)
+	}
+	if item.CreateTime != "1777377844000" {
+		t.Fatalf("CreateTime = %q, want numeric timestamp string", item.CreateTime)
+	}
+	if item.UpdateTime != "1777556451000" {
+		t.Fatalf("UpdateTime = %q, want numeric timestamp string", item.UpdateTime)
+	}
+	if item.Amount != "1.60" {
+		t.Fatalf("Amount = %q, want 1.60", item.Amount)
+	}
+}