Fix NEXT_PUBLIC_API_BASE_URL not applying in production build

NEXT_PUBLIC_* vars are inlined at build time, not runtime.
Pass as Docker build arg so Next.js picks it up during bun run build.

https://claude.ai/code/session_01Xmxm2QLgFBgRJyYD6VukR6

docker-compose.yml

@@ -11,8 +11,8 @@ services:
     build:
       context: ./
       dockerfile: ./docker/webapp.Dockerfile
-    environment:
-      - NEXT_PUBLIC_API_BASE_URL=https://api.cv.alves.world
+      args:
+        - NEXT_PUBLIC_API_BASE_URL=https://api.cv.alves.world
     networks:
       - dokploy-network
       - cvfs-network