Dockerizing my existing mongo database in MERN App

I have created MERN application a little bit ago and deployed it on local server with pm2 package and run API and React App as separate services. As I wanted to dockerize everything, I created Dockerfile in React App and in API and then created docker-compose.yaml:

version: "3.9"

services:
  mongo:
    image: mongo:latest
    ports:
      - 27017:27017
    volumes:
      - ./mongo-db:/var/lib/mongo/data
    networks:
      - project-network
  api:
    container_name: project_api
    restart: unless-stopped
    image: project_api:1.0.0
    build:
      context: back-end
      dockerfile: Dockerfile
    ports:
      - 4001:4001
    networks:
      - project-network
    depends_on:
      - mongo
  client:
    container_name: project_client
    restart: unless-stopped
    image: project_client:1.0.0
    build:
      context: front-end
      dockerfile: Dockerfile
    ports:
      - 3000:3000
    networks:
      - project-network
    depends_on:
      - api

networks:
  project-network:

Everything works perfectly OK and there are no errors in execution of this. The problem is that I already have in my local mongodb too many collected data that of course are not presented in the dockerized application (as mongodb is running its own container service). How I can have my data in the application? I see 3 options:

1. Somehow copy the data inside the container
2. Run the mongodb service outside of the composed image
3. Manually to re-enter all data (it is very big so for me it is not very good option)

For every option there are some questions. If the best option is 1. how I can save the data in container? Also am I going to loose all the data when I re-create some part of the application and use docker compose build again?

If option is 2., how I can access local mongodb inside containers(mongodb://localhost:27017/db_name)? Probably with shared network?

I would appreciate any kind of best advices how should proceed in this situation when I decided to dockerize application some time after it is already in use and have already collected big amount of data.