refactor(new-game): modernize UI, remove player selects

- Refactored New Game screen to use a modern, card-like, dark-themed layout
- Removed select dropdowns for previous players, now only datalist+input for player names
- Updated paddings, backgrounds, borders, and font sizes for a visually consistent, modern look
- No logic changes, only markup and style

Refs #1

package.json

@@ -3,7 +3,7 @@
   "type": "module",
   "version": "0.0.1",
   "scripts": {
-    "dev": "astro dev",
+    "dev": "astro dev --host",
     "build": "astro build",
     "preview": "astro preview",
     "astro": "astro"