fix: minor fixes, tweaks, refactors

[tazlin]

Following up on #22:

• Introduced hordelib as a mypy pre-commit hook dep, allowing analysis of the types from that library.
• Fixed an import error that could occur with mypy (see mypy.ini)
• Resolved a couple of indev comments/messages in the code
• Refactored _api_call_loop to use asyncio tasks
• Made it so torch is loaded only in child processes, potentially avoiding some shared-resource confusion.