add 2 new CI jobs which run under a new Nix Buffers CI workflow (we also cache the nix store locally)
-- nix flake check on ubuntu
-- nix flake check on mac
enable all CI workflows to be manually triggered from the actions panel
clean up flake.nix
speed up nix builds by providing libgit and openssl, instead of building from source
The following changes were made:
Nix Buffers CIworkflow (we also cache the nix store locally) --nix flake checkon ubuntu --nix flake checkon macactionspanelflake.nixnix flake checknow does the following:nixfiles are correctly formatted