chore: Removed duplicate Nix install

feat: Update nix-build.yml

chore: Update and rename nix-build to nix-build.yml

chore: Delete .github/workflows/nix-test

Create nix-build

feat: Create nix-test as proof-of-concept

chore: Wrote `README.md`

test: Nix store caching

chore: Removed multi-platform builds

bugfix: Repository's primary branch is actually `master`

test: Checking to see if auto builds (with cache) works

feat: Functional Dockerfile

feat: Boilerplate