add test event handlers

frontend/script.js

@@ -59,6 +59,14 @@
             player.addChild(bigCastButton);
         });
 
+        player.on("loadedmetadata", () => {
+            console.log("loadedmetadata");
+        });
+        
+        player.on("posterchange", () => {
+            console.log("posterchange");
+        });
+
         const smallCastButton = new Button(player, cbutton);
         smallCastButton.addClass("fab");
         smallCastButton.addClass("fa-chromecast");