Update JavaScript and TypeScript codes for all chapters, rename JavaScript and TypeScript import folder to modules (#402)

* Update JavaScript and TypeScript codes

* Rename JavaScript and TypeScript import folder to modules

codes/javascript/chapter_stack_and_queue/array_stack.js

@@ -7,49 +7,48 @@
 
 /* 基于数组实现的栈 */
 class ArrayStack {
-    stack;
+    #stack;
     constructor() {
-        this.stack = [];
+        this.#stack = [];
     }
     
     /* 获取栈的长度 */
     get size() {
-        return this.stack.length;
+        return this.#stack.length;
     }
 
     /* 判断栈是否为空 */
     empty() {
-        return this.stack.length === 0;
+        return this.#stack.length === 0;
     }
 
     /* 入栈 */
     push(num) {
-        this.stack.push(num);
+        this.#stack.push(num);
     }
 
     /* 出栈 */
     pop() {
         if (this.empty())
             throw new Error("栈为空");
-        return this.stack.pop();
+        return this.#stack.pop();
     }
 
     /* 访问栈顶元素 */
     top() {
         if (this.empty())
             throw new Error("栈为空");
-        return this.stack[this.stack.length - 1];
+        return this.#stack[this.#stack.length - 1];
     }
 
     /* 返回 Array */
     toArray() {
-        return this.stack;
+        return this.#stack;
     }
 };
 
 
 /* Driver Code */
-
 /* 初始化栈 */
 const stack = new ArrayStack();