feat: docker-compose - added mapping of package*.json files from the host to...

feat: docker-compose - added mapping of package*.json files from the host to the container, added comments describing what is happening and why

docker-compose.yml

@@ -15,7 +15,12 @@ services:
     volumes:
       # changes in host's ./backend directory will be propagated to the container
       - ./backend:/usr/src/app
+      # this will let us add packages during development without rebuilding the image
+      # - we then need to install added packages (run 'npm i') inside the container in the folder '/usr/src'
+      - ./backend/package.json:/usr/src/package.json
+      - ./backend/package-lock.json:/usr/src/package-lock.json
       # this prevents our host files from overriding container's node_modules
+      # – some packages may be platform specific so we always want to run 'npm i' in the container when new package is added
       - exclude-server:/usr/src/app/node_modules/
     environment:
       - PORT=${SERVER_PORT}