Fix frontend black screen issue in docker-compose setup

Change frontend environment from 'compose' to 'local' as 'compose' is not
a valid environment in the frontend startup script. Expose port 3000 for
the mina-node HTTP API to allow frontend to connect to the backend.

This resolves the black screen issue where the frontend failed to start
because of an invalid environment configuration.

Author: directcuteo

CHANGELOG.md

@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Fixed
+
+- **Docker Compose**: Fix frontend black screen issue by changing environment
+  from `compose` to `local` and exposing port 3000 for mina-node HTTP API
+  ([#1649](https://github.com/o1-labs/mina-rust/pull/1649))
+
 ## [0.18.0] - 2025-11-04
 
 ### OCaml node

docker-compose.yml

@@ -12,6 +12,7 @@ services:
     volumes:
       - ./mina-workdir:/root/.mina:rw
     ports:
+      - "3000:3000"
       - "${MINA_LIBP2P_PORT:-8302}:${MINA_LIBP2P_PORT:-8302}"
     environment:
       MINA_LIBP2P_EXTERNAL_IP: "${MINA_LIBP2P_EXTERNAL_IP:-}"
@@ -20,6 +21,6 @@ services:
   frontend:
     image: o1labs/mina-rust-frontend:${MINA_FRONTEND_TAG:-latest}
     environment:
-      MINA_FRONTEND_ENVIRONMENT: compose
+      MINA_FRONTEND_ENVIRONMENT: local
     ports:
       - "8070:80"