use the placeholder player model

public/menu/index.html

@@ -0,0 +1,26 @@
+<style>
+  html {
+    background-color: black;
+    color: white;
+    font-family: sans-serif;
+  }
+  a:link, a:hover, a:active, a:visited {
+    color: white;
+  }
+</style>
+<h1>Take control of a unit:</h1>
+<ul id="links"></ul>
+<script>
+  websocket = new WebSocket(`ws://${window.location.hostname}:1280/ws`)
+  websocket.onopen = () => { websocket.send(JSON.stringify({ action: 'entities' })) }
+  websocket.onmessage = (event) => {
+    const message = JSON.parse(event.data)
+    const entityIds = message?.entities
+    if (entityIds == null) { return }
+
+    websocket.close()
+    let links = ''
+    entityIds.forEach((entityId) => links += `<li><a href="/?id=${encodeURI(entityId)}">${entityId}</a></li>`)
+    document.getElementById('links').innerHTML = links
+  }
+</script>