feat(js): add solution and documentation for easy challenge 6 - Palindrome checker

Author: IbatoLionDev

1-EASY/JavaScript/6-palindrome-checker/article.md

@@ -0,0 +1,54 @@
+# Challenge Description and Solution
+
+## English Version
+
+### Challenge Description
+Create a function that determines if a string is a palindrome, meaning it reads the same forwards and backwards.
+
+### Code Explanation
+The `isPalindrome` function converts the string to lowercase and removes spaces for comparison. It then compares the string with its reverse to determine if it is a palindrome.
+
+### Relevant Code Snippet
+
+```javascript
+function isPalindrome(s) {
+    const normalized = s.toLowerCase().replace(/\s+/g, '');
+    return normalized === normalized.split('').reverse().join('');
+}
+```
+
+### Example Usage
+
+```javascript
+const testStrings = ["radar", "hello", "level", "world"];
+testStrings.forEach(str => {
+    console.log(`'${str}' is palindrome: ${isPalindrome(str)}`);
+});
+```
+
+---
+
+## Versión en Español
+
+### Descripción del Reto
+Crea una función que determine si una cadena es un palíndromo, es decir, que se lee igual de izquierda a derecha y de derecha a izquierda.
+
+### Explicación del Código
+La función `isPalindrome` convierte la cadena a minúsculas y elimina espacios para hacer la comparación. Luego compara la cadena con su reverso para determinar si es un palíndromo.
+
+### Fragmento de Código Relevante
+
+```javascript
+function isPalindrome(s) {
+    const normalized = s.toLowerCase().replace(/\s+/g, '');
+    return normalized === normalized.split('').reverse().join('');
+}
+```
+
+### Ejemplo de Uso
+
+```javascript
+const testStrings = ["radar", "hello", "level", "world"];
+testStrings.forEach(str => {
+    console.log(`'${str}' es palíndromo: ${isPalindrome(str)}`);
+});

1-EASY/JavaScript/6-palindrome-checker/proposed-solution/main.js

@@ -0,0 +1,12 @@
+// Challenge: Create a function that determines if a string is a palindrome, meaning it reads the same forwards and backwards.
+
+function isPalindrome(s) {
+    const normalized = s.toLowerCase().replace(/\s+/g, '');
+    return normalized === normalized.split('').reverse().join('');
+}
+
+// Example usage
+const testStrings = ["radar", "hello", "level", "world"];
+testStrings.forEach(str => {
+    console.log(`'${str}' is palindrome: ${isPalindrome(str)}`);
+});