Update demo site header

Author: ota-meshi

explorer-v2/src/routes/index.svelte

@@ -7,7 +7,8 @@
 </script>
 
 <svelte:head>
-	<title>Home</title>
+	<title>svelte-eslint-parser</title>
+	<meta name="description" content="Svelte parser for ESLint" />
 </svelte:head>
 
 <AstExplorer />

explorer-v2/src/routes/playground.svelte

@@ -7,7 +7,7 @@
 </script>
 
 <svelte:head>
-	<title>Playground</title>
+	<title>Playground | svelte-eslint-parser</title>
 </svelte:head>
 
 <ESLintPlayground />

explorer-v2/src/routes/scope.svelte

@@ -7,7 +7,7 @@
 </script>
 
 <svelte:head>
-	<title>Scope</title>
+	<title>ScopeManager | svelte-eslint-parser</title>
 </svelte:head>
 
 <ScopeExplorer />