This commit introduces a capsule type, `TypeType`, which is used to
extricate type information from the console-only `type` function. In
combination with the `TypeType` mark, this allows us to restrict the use
of this function to top-level display of a value's type. Any other use
of `type()` will result in an error diagnostic.
This is part of a general effort to move all of Terraform's non-library
package surface under internal in order to reinforce that these are for
internal use within Terraform only.
If you were previously importing packages under this prefix into an
external codebase, you could pin to an earlier release tag as an interim
solution until you've make a plan to achieve the same functionality some
other way.