Add a clean nix/nixos development enviroment

[Eveeifyeve]

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Description

Adds a nix/nixos development with automation though github actions with

Motivation and Context

This change is required because there is currently no default dev enviroment for nix/nixos It solves having an environment to use when developing ferrum there was previously a pr for adding a flake below, but there was a couple problems one it uses flake utils which is a non module based system which means it makes it harder to make things compatible plus is a non nix way of doing, two building the package inside of the devshell is not really required as the user can run cargo build --release and then use the bin produced, three it tries to add back the cargo lock file which is only good if your producing a library but ferrumc is producing a binary so it's an unneeded file.

Follow up #125.

How has this been tested?

Local using direnv and nix develop as well as nix flake check plus I have also built in a flake check for each pr that is created.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (restructuring code, without changing its behavior)
• Add repository changes

Checklist:

• My code follows the code style of this project.
• I have added tests to cover my changes.
• All new and existing tests passed.
• Clippy passes with no warnings.