Standardize event names to be consistent with @headlessui-react

Was previously using Vue names since Vue was the primary reference while porting, but as the public API is closer to the React one it makes sense to use that.

Fixes #8

src/routes/radio-group/radio-group.svelte

@@ -20,15 +20,12 @@
       description: "You are the only one able to access this project",
     },
   ];
-  let active;
+  let active: typeof access[number];
 </script>
 
 <div class="p-12 max-w-xl">
   <a href="/">Link before</a>
-  <RadioGroup
-    value={active}
-    on:updateValue={(event) => (active = event.detail)}
-  >
+  <RadioGroup value={active} on:change={(event) => (active = event.detail)}>
     <fieldset class="space-y-4">
       <legend>
         <h2 class="text-xl">Privacy setting</h2>