The extract_terraform move #1721 proposed already landed on v8 via the #1737
decomposition (extractors/terraform.py exists, extract.py re-exports it, and
extractors/LANGUAGE_EXTRACTORS registers it), so the code move is a no-op now.
But the regression test @Cekaru added with it had no equivalent on v8. Salvage
and generalize it: sweep every LANGUAGE_EXTRACTORS entry and assert graphify.
extract re-exports the SAME object (facade identity) and the registry maps to
it (registry identity), plus the concrete terraform anchor from the PR. This
institutionalizes the re-export-identity guarantee the split relies on, so a
future move that forgets a facade re-export fails loudly.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
