chore: add missing auth utils and public routes

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

packages/server/src/routes/public.routes.ts

@@ -0,0 +1,45 @@
+import { Router, IRouter } from 'express';
+import { prizeConfigService } from '../services/prize-config.service';
+import { participantService } from '../services/participant.service';
+
+const router: IRouter = Router();
+
+/**
+ * GET /api/public/prizes
+ * Public read-only prize configuration (for screen display)
+ */
+router.get('/prizes', (_req, res, next) => {
+  try {
+    const config = prizeConfigService.getFullConfig();
+    return res.json({
+      success: true,
+      data: config,
+    });
+  } catch (error) {
+    next(error);
+  }
+});
+
+/**
+ * GET /api/public/participants
+ * Public read-only participant list (for screen display)
+ */
+router.get('/participants', (_req, res, next) => {
+  try {
+    const participants = participantService.getAll();
+    const stats = participantService.getStats();
+    return res.json({
+      success: true,
+      data: {
+        count: participants.length,
+        tagDistribution: stats.tagDistribution,
+        participants,
+      },
+    });
+  } catch (error) {
+    next(error);
+  }
+});
+
+export default router;
+