feat: initial elysium idle game prototype

Sets up the full monorepo with pnpm workspaces. Includes shared types
package, Hono API with Discord OAuth/JWT auth, Prisma v6 + MongoDB
Atlas, and React + Vite frontend with game loop, five tabs, and
Discord-linked save/load.

apps/api/src/middleware/auth.ts

@@ -0,0 +1,23 @@
+import type { Context, Next } from "hono";
+import { verifyToken } from "../services/jwt.js";
+
+export const authMiddleware = async (context: Context, next: Next): Promise<void> => {
+  const authorization = context.req.header("Authorization");
+
+  if (!authorization?.startsWith("Bearer ")) {
+    context.status(401);
+    context.json({ error: "Missing or invalid Authorization header" });
+    return;
+  }
+
+  const token = authorization.slice(7);
+
+  try {
+    const payload = verifyToken(token);
+    context.set("discordId", payload.discordId);
+    await next();
+  } catch {
+    context.status(401);
+    context.json({ error: "Invalid or expired token" });
+  }
+};