add docker

docker-compose.yml

@@ -0,0 +1,22 @@
+version: "3.9"
+
+services:
+  app:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    image: magikarp-collection:latest
+    environment:
+      - NODE_ENV=production
+      # Internal Next.js port (container). Do not change unless you change Dockerfile.
+      - PORT=3000
+      # Forward any API keys if needed
+      - NEXT_PUBLIC_POKEMON_TCG_API_KEY=${NEXT_PUBLIC_POKEMON_TCG_API_KEY}
+      - POKEMON_TCG_API_KEY=${POKEMON_TCG_API_KEY}
+    ports:
+      # Select host port via APP_PORT env var; default 3000
+      - "${APP_PORT:-3000}:3000"
+    volumes:
+      # Persist local cache JSON files
+      - ./data:/app/data
+    restart: unless-stopped