Better devex

Using ES6 modueles and adding a JS LSP to `flake.nix`

global/loadin.mjs

@@ -0,0 +1,8 @@
+export function loadHTML(elementId, url) {
+    fetch(url)
+        .then((response) => response.text())
+        .then((data) => {
+            document.getElementById(elementId).innerHTML = data;
+        })
+        .catch((error) => console.error("Error loading HTML:", error));
+}