build(app): optimize app docker image size

export app static pages and deploy with Nginx image, instead of host `next start` service

docker-compose.yaml

@@ -31,7 +31,7 @@ services:
     depends_on:
       - perplexica-backend
     ports:
-      - 3000:3000
+      - 3000:80
     networks:
       - perplexica-network