Add Docker support and improve Instagram login flow

[dave-73]

Adds containerized execution with Docker Compose and improves login reliability.

Changes:

• Add Dockerfile and docker-compose.yml for isolated execution
• Run container as a non-root user and persist runtime data under ./data
• Ignore cookies, local data, and generated exports
• Use instagrapi for current Instagram login and 2FA support
• Add fallback for importing an authenticated Cookie header
• Add httpx[http2] dependency because the scraper enables HTTP/2
• Update README with Docker and authentication notes

Validation:

• python -m py_compile main.py login.py
• docker compose config
• docker compose build

[kaifcodec]

@dave-73 Thank you for opening this PR, I was little bit busy on my other repositories so I forgot to take a look on this.

I see 280 additions with this PR, can you confirm that the login works as expected when you tested it yourself?

[dave-73]

Thanks for taking a look!

Yes, I tested it locally. The Docker setup builds and runs correctly, and authentication works in my testing. Instagram’s 2FA/login flow can change or behave differently depending on the account, so I added the Cookie header fallback as a reliable alternative.

The cookie-based authentication has worked consistently for me, and I’m currently using it without issues.