Release 0.1.2

Patch release. Fixes the fail-closed mif-guard hook so it no longer blocks a markdown file whose only type: is nested under another key (for example an auto-memory file's metadata.type). The genre-signal detection now anchors type, ontology, and diataxis_type to the top level of the frontmatter. Real MIF genre documents are still validated and non-conformant ones are still blocked. Adds a regression test and fixture. See #11 and #12.