[2051] Core Plugin Audit

[Rixxan]

Broken out of #2068

Description

This is a full-pass update to the core plugin files, containing a major SemVer-compliant logic overhaul to the files. These updates are intended to optimize existing code, update older Python 2 style code to more updated standards, and increase readability and compatibility.

Type of change

• Rewrite of Existing Code

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Multiple install runs, clean installs, self-updates, and others made to confirm functionality, including under a variety of existing pre-install situations.
• All PyTest tests pass
• Tested by the EDMC Internal Alpha Group and initial bugs fixed.

[C1701D]

LGTM

[Athanasius]

Slightly strange choice there to regress from dict to Dict on types, and e.g. str | None to Optional[str]. That's going from the newer forms to the older. The idea is to have to import less from typing, not more. Things like Dict and Optional were necessary in typing before proper support was added in later Python versions.