Re-translate the Japanese version (#1871)

* Retranslate Japanese docs with GPT-5.4

* Retranslate Japanese code with GPT-5.4

ja/codes/csharp/utils/ListNode.cs

@@ -0,0 +1,32 @@
+// File: ListNode.cs
+// Created Time: 2022-12-16
+// Author: mingXta (1195669834@qq.com)
+
+namespace hello_algo.utils;
+
+/* 連結リストノード */
+public class ListNode(int x) {
+    public int val = x;
+    public ListNode? next;
+
+    /* 配列をデシリアライズして連結リストに変換する */
+    public static ListNode? ArrToLinkedList(int[] arr) {
+        ListNode dum = new(0);
+        ListNode head = dum;
+        foreach (int val in arr) {
+            head.next = new ListNode(val);
+            head = head.next;
+        }
+        return dum.next;
+    }
+
+    public override string? ToString() {
+        List<string> list = [];
+        var head = this;
+        while (head != null) {
+            list.Add(head.val.ToString());
+            head = head.next;
+        }
+        return string.Join("->", list);
+    }
+}