Fix global declaration of staticRoot and webRoot

These variables were intended to be globals declare in the global
namespace. That this ends up on the window object is an implementation
detail of JavaScript. Remove the window. prefix put in front of
staticRoot and webRoot and include the global declaration in the
TypeScript module.

packages/controller/web/index.html

@@ -20,8 +20,8 @@
 			}
 		</style>
 		<script>
-			window.webRoot = new URL("__WEB_ROOT__", document.location).pathname;
-			window.staticRoot = new URL("__STATIC_ROOT__", document.location).pathname;
+			webRoot = new URL("__WEB_ROOT__", document.location).pathname;
+			staticRoot = new URL("__STATIC_ROOT__", document.location).pathname;
 			function scriptError() {
 				let bootstrapMsg = document.getElementById("bootstrap-msg");
 				bootstrapMsg.textContent = "Error loading main bundle, see web console for details.";