This opens up the Delphi IDE with the correct KEYMAN_ROOT environment,
which allows for debugging. This is very helpful when working with
multiple worktrees, and also helps to avoid editing a project in the
wrong tree.
The new version of `langtags.json` added a new `_conformance` record
at the top of the file. This change adjusts the indexes where we expect
the `_version` record. It also introduces a const for the index of the
version record to make future updates easier.
