Native-vision user turns persist inline base64 in history text, so the
served user text never equals the Desktop optimistic @image ref and the
optimistic bubble is re-appended below every finished reply.
Display-only projection in _history_to_messages for role=user rows:
verified local image parts become @image: refs, stored/model content
untouched. Ambiguous or missing images keep inline form.
The session store's text-only projection appends one `[screenshot]`
line per image part, so flattened rows are projected too: trailing
placeholders are peeled (one per projected ref, else unprojected) and
dropped, mirroring the Desktop's extractImageRefs.
Closes#120083
23de088b6a