Safe DOCX posture
w:comment comment content emission
Each comment carries deterministic metadata: sequential ids in document
order, author falling back note.author → meta.author → 'safe-docx' with
derived initials, dates only from DraftingNoteSpec.dateIso or
meta.createdIso (never the clock), and a w14:paraId derived from the
comment id so commentsExtended entries pair up by construction.
The compiled checker additionally validates bounded canonical IDs and requires
definitions to be direct w:comments children. Extension thread graphs remain
outside scope.