moved application.js into packs directory

Author: David Zuckerman

app/javascript/packs/application.js

@@ -0,0 +1,14 @@
+// Entry point for the build script in your package.json
+
+window.addEventListener('load', () => {
+  const navMenuCheckbox = document.getElementById('nav-menu')
+  if (!navMenuCheckbox) {
+    console.log('navMenuCheckbox not found')
+    return
+  }
+  navMenuCheckbox.addEventListener('keydown', (e) => {
+    if (e.code === 'Enter') {
+      navMenuCheckbox.checked = !navMenuCheckbox.checked
+    }
+  })
+})