fix worker + start create modal with logic

frontend/lib/actions.ts

@@ -0,0 +1,15 @@
+"use server"
+
+export async function createSandbox(body: {
+  type: string
+  name: string
+  visibility: string
+}) {
+  const res = await fetch("http://localhost:8787/api/sandbox/create", {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+    },
+    body: JSON.stringify(body),
+  })
+}