[DevOps] Containerize the technology stack

[tomvothecoder]

Description

• Closes [DevOps] Containerize the technology stack #23

Steps to Complete

• Create Dockerfiles for backend
  • Backend
  • Frontend -- in progress
• Add docker-compose.dev.yml to orchestrate development mode for backend and frontend
• Add docker-compose.yml to orchestrate production mode for backend, frontend, and Traefik
• Figure out cookie storage for user authentication -- in progress
• Configure Traefik for HTTPS routing and local certificate handling
• Update FastAPI CORS and cookie settings for secure HTTPS operation
• Verify:
  • Frontend served at https://localhost
  • API requests proxy correctly to backend
  • Cookies and CORS function as expected
• Add setup documentation and Spin deployment notes

Checklist

• Code follows project style guidelines
• Self-reviewed code
• No new warnings
• Tests added or updated (if needed)
• All tests pass (locally and CI/CD)
• Documentation/comments updated (if needed)
• Breaking change noted (if applicable)

Deployment Notes (if any)