feat: add linkedlist_stack in js to doc

docs/chapter_stack_and_queue/stack.md

@@ -390,7 +390,63 @@ comments: true
 === "JavaScript"
 
     ```js title="linkedlist_stack.js"
-    
+    /* 基于链表实现的栈 */
+    class LinkedListStack {
+        #stackPeek;  // 将头结点作为栈顶
+        #stkSize = 0;   // 栈的长度
+
+        constructor() {
+            this.#stackPeek = null;
+        }
+
+        /* 获取栈的长度 */
+        get size() {
+            return this.#stkSize;
+        }
+
+        /* 判断栈是否为空 */
+        isEmpty() {
+            return this.size == 0;
+        }
+
+        /* 入栈 */
+        push(num) {
+            const node = new ListNode(num);
+            node.next = this.#stackPeek;
+            this.#stackPeek = node;
+            this.#stkSize++;
+        }
+
+        /* 出栈 */
+        pop() {
+            const num = this.peek();
+            if (!this.#stackPeek) {
+                throw new Error("栈为空！");
+            }
+            this.#stackPeek = this.#stackPeek.next;
+            this.#stkSize--;
+            return num;
+        }
+
+        /* 访问栈顶元素 */
+        peek() {
+            if (!this.#stackPeek) {
+                throw new Error("栈为空！");
+            }
+            return this.#stackPeek.val;
+        }
+
+        /* 将链表转化为 Array 并返回 */
+        toArray() {
+            let node = this.#stackPeek;
+            const res = new Array(this.size);
+            for (let i = res.length - 1; i >= 0; i--) {
+                res[i] = node.val;
+                node = node.next;
+            }
+            return res;
+        }
+    }
     ```
 
 === "TypeScript"