JS: Add a setOption handler that can toggle the bg/background option

assets/js/commands.js

@@ -0,0 +1,16 @@
+document.addEventListener("DOMContentLoaded", () => {
+    const commandBar = document.querySelector("command-bar");
+
+    commandBar.addEventListener("setOption", event => {
+        console.log("SetOption", event);
+        switch (event.option) {
+            case "bg":
+            case "background":
+                const value = event.newValue;
+                if (value === "dark" || value === "light") {
+                    document.querySelector(":root").setAttribute("color-scheme", value);
+                }
+                break;
+        }
+    });
+});