chore: add docker-compose, .gitignore and README

Infrastructure files for staging deployment pipeline.
The post-receive hook on the staging server will build and
deploy automatically when PRs are merged to main.

Made-with: Cursor

docker-compose.yml

@@ -0,0 +1,9 @@
+services:
+  frontend:
+    build: .
+    image: encoach-frontend:latest
+    container_name: encoach-frontend
+    restart: unless-stopped
+    ports:
+      - "3000:3000"
+    env_file: .env