feat: add about page, global stats counter, and blitz screen updates

- Create about page with game modes, technologies, and paliers
- Add stats API endpoint for global game counter
- Update home screen with emoji-based tier system (🌱-🚀)
- Rewrite BlitzScreen to match new puzzle-based win/lose phases
- Add simple-icons package for tech stack icons
- Update metadata with wikirush.xyz domain
- Fix em dashes to hyphens throughout codebase
- Update footer with privacy and about links

app/api/stats/route.ts

@@ -0,0 +1,17 @@
+import { NextResponse } from "next/server";
+import { prisma } from "../../../lib/prisma";
+
+export const revalidate = 60; // revalide toutes les 60s
+
+export async function GET() {
+  const todayStart = new Date();
+  todayStart.setHours(0, 0, 0, 0);
+
+  const todayCount = await prisma.game.count({
+    where: { playedAt: { gte: todayStart } },
+  });
+
+  const totalCount = await prisma.game.count();
+
+  return NextResponse.json({ today: todayCount, total: totalCount });
+}