A claimed command is now a CommandChipNode on the draft's leading seat
instead of styled literal text. The submit machine follows the chip: it
holds the claim while the chip leads the document, releases it when the
chip is deleted or displaced, and re-enters claimed when history
restores the chip. Deleting at the chip's edge takes two steps: the
first Backspace or Delete selects the chip, the next removes it.
The claim-token decoration transform and the text-reference precedence
rule are removed with the literal token.
Yichen Jiang
98d93db18f