First stab at new Python bindings

[mavam]

This PR includes the first infrastructure work for a revamped version of Threat Bus in the form of VAST Python layer, sparked by two recent hackathons.

:memo: Checklist

• [x] Simple asyncio MVP
• [x] In-memory fabric backbone
• [x] MISP 0mq data acqusition
• [x] MISP REST API initilization
• [x] MISP-to-STIX: complete event conversion
• [x] VAST-to-STIX: convert query results to STIX
• [x] Package via Poetry

:dart: Review Instructions

To review this, make sure you have a VAST instance running locally. The tooling is not yet capable of spawning one, but that will come next.

The primary objective for the review would actually be the scaffolding, not so much the functions (which are still alpha). Please take a look at the CI workflow, the project setup (pyproject.toml), and the Poetry-based workflows. The README should make you get started so that you can enter environment to invoke an example.