@spec config(
  binary(),
  keyword()
) :: binary()

Gets a Git configuration value (local → global → system).

Accepts an optional cd: option to scope the lookup to a specific repository directory.

@spec config_global(
  binary(),
  keyword()
) :: binary()

Gets a Git configuration value from the global scope.

Accepts an optional cd: option (kept for signature parity with config/2; ignored at the global scope).

@spec config_local(
  binary(),
  keyword()
) :: binary()

Gets a Git configuration value from the local (repo) scope.

Accepts an optional cd: option to scope the lookup to a specific repository directory.

@spec get_git_user_email() :: binary() | nil

Returns the configured Git user email, or nil if not set.

@spec get_git_user_name() :: binary() | nil

Returns the configured Git user name, or nil if not set.

@spec get_hostname() :: binary()

Returns the machine's hostname.

@spec get_system_user_email() :: binary()

Returns the current system user email from the USER_EMAIL env variable, falling back to "user@domain.com".

@spec get_system_user_name() :: binary()

Returns the current system user name.

@spec get_user_info() :: map()

Returns a map with the current Git user information.

Falls back to system user information if Git is not configured.

@spec set_user_info(binary(), binary()) :: :ok | {:error, binary()}

Sets Git user name, email, and URL rewrite rules globally.