feat: initialize Annual Gala Interactive System monorepo

- Set up pnpm workspace with 4 packages: shared, server, client-mobile, client-screen
- Implement Redis atomic voting with Lua scripts (HINCRBY + distributed lock)
- Add optimistic UI with IndexedDB queue for offline resilience
- Configure Socket.io with auto-reconnection (infinite retries)
- Separate mobile (Vant) and big screen (Pixi.js) dependencies

Tech stack:
- Frontend Mobile: Vue 3 + Vant + Socket.io-client
- Frontend Screen: Vue 3 + Pixi.js + GSAP
- Backend: Express + Socket.io + Redis + Prisma/MySQL

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/server/src/routes/admin.routes.ts

@@ -0,0 +1,57 @@
+import { Router, IRouter } from 'express';
+
+const router: IRouter = Router();
+
+/**
+ * GET /api/admin/stats
+ * Get system statistics
+ */
+router.get('/stats', async (_req, res, next) => {
+  try {
+    // TODO: Implement admin stats
+    return res.json({
+      success: true,
+      data: {
+        totalUsers: 0,
+        totalVotes: 0,
+        activeConnections: 0,
+      },
+    });
+  } catch (error) {
+    next(error);
+  }
+});
+
+/**
+ * POST /api/admin/draw/start
+ * Start a lucky draw
+ */
+router.post('/draw/start', async (_req, res, next) => {
+  try {
+    // TODO: Implement draw start
+    return res.json({
+      success: true,
+      message: 'Draw started',
+    });
+  } catch (error) {
+    next(error);
+  }
+});
+
+/**
+ * POST /api/admin/draw/stop
+ * Stop the current draw
+ */
+router.post('/draw/stop', async (_req, res, next) => {
+  try {
+    // TODO: Implement draw stop
+    return res.json({
+      success: true,
+      message: 'Draw stopped',
+    });
+  } catch (error) {
+    next(error);
+  }
+});
+
+export default router;