The feature catalog had a row for View › Read Mode and none for the
items in Read Mode's own View menu, so the parity checklist did not
count them. Column Width maps to view.readColumnWidth, which is live.
Page Color maps to view.readPageColor and Layout to view.readLayout;
neither command exists on main, so both are listed as missing.
docs/parity-checklist.md is regenerated with `cargo xtask parity`:
503 of 520 catalog features have commands (96.7%).