feat: initial Vite/React frontend service template

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

index.html

@@ -0,0 +1,14 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>${REPO_NAME}</title>
+    <!-- Runtime config, generated at container start (docker-entrypoint.d/10-config.sh). -->
+    <script src="/config.js"></script>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script type="module" src="/src/main.tsx"></script>
+  </body>
+</html>