Add React + Vite port of the logo generator

Full React port sharing src/logo.js core (shadow geometry, CSS
output, defaults, font list). App.jsx holds the entire state in a
single useState object; controlled inputs drive the live render and
generated CSS. Keeps the accessibility markup (labels, aria,
<details>/<summary>, focus rings) from the html/vanilla versions;
reset restores defaults via the form's onReset.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html lang="de">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1">
+  <title>Logo-Generator</title>
+  <link href="https://fonts.googleapis.com/css2?family=Anton&family=Bowlby+One&family=Bebas+Neue&family=Bungee&family=Passion+One:wght@900&family=Ultra&display=swap" rel="stylesheet">
+</head>
+<body>
+  <div id="root"></div>
+  <script type="module" src="/src/main.jsx"></script>
+</body>
+</html>