Intelligence Service MVP Java Spring Boot setup

[milesha]

Contains #169

Motivation

We want to perform and store chats with the AI Mentor.

Description

This PR adds following entities and functionality:

• Session. You can:
  • create a new session
  • get a list of all existing sessions for a given user
• Message. You can:
  • get a list of all existing messages in a given session
  • send a message into a session and get response from an OpenAI instance

Testing Instructions

• Start the application-server and intelligence service

Checklist

General

• PR title is clear and descriptive
• PR description explains the purpose and changes
• Code follows project coding standards
• Self-review of the code has been done
• Changes have been tested locally
• Screenshots have been attached (if applicable)
• Documentation has been updated (if applicable)

Server (if applicable)

• Code is performant and follows best practices
• No security vulnerabilities introduced
• Proper error handling has been implemented
• Added tests for new functionality
• Changes have been tested in different environments (if applicable)

[FelixTJDietrich]

I think it should be good now :)