Controls committed on blur, which turned leaving a field into a durable,
revision-fenced document write the user could neither preview nor undo, and
silently discarded a draft the field did not accept.
A card's form now owns the staged text every control renders, and Save is the
only point where drafts become writes. Reset stages the composed default the
same way; an invalid draft blocks the save with its reason instead of being
dropped; Discard drops the drafts; a collapsed card marks that it holds some.
The Host stays the only authority on whether a value was accepted, so the save
reads the section back and keeps the drafts of a save that did not land.
Three scenarios over the real wire: the cards this deployment's exposed
namespaces produce, one field edited down to the settings document with the
override badge that layering produces, and the reset that clears it back to
the composed default.
Every other settings golden gains the same nav entry and nothing else.
Dudu-0223