Support for retrieving env and run of commands

[dennybaa]

Hey @cebarks , thank you - you project looks cool.

If I may share a few words of feedback... The core functionality is great, this feels like a good substitution for stow. The tera templating is very useful and the whole concept of roles and hosts is very useful and not too heavy at the same time.

Again being not too heavy and opinionated as chezmoi it would be nice to add some dynamic nature to the project:

• Defining vars statically in toml is absolutely okay, but at the same time it would be cool to load dotenvy file

  [vars]
  _.file = [
     "./.env",
     { path = "{{ config_root }}/.env.{{ role }}"  },
  ]

  Smth like mise does.

• Add smth like {{ run "command" }} to be able to substitute output dynamically into terra files...

What do you think @cebarks , maybe it's be on your list already?

[cebarks]

@dennybaa I like this idea, it would be handy for defining secrets and keeping them out of your git repo.

I'd maybe even say that we should go a step further and allow arbitrary scripts to run and the result to be stored to a var, do you think this would also be helpful?

[dennybaa]

@cebarks Yeah, why not absolutely like mise exec() can be useful https://mise.jdx.dev/templates.html#general-functions, but there definitely should be just a minimal set of functions - to keep dotfiles manager simple.