The keyset rows were a stack of flex divs with no column labels. They are
now a fixed-layout table like the TAR table: a thead with # (keyset number,
with its tooltip), KIc, KID, KIc key, KID key, Counter and the action
column, and <tr> rows of py-1 px-2 cells with w-full inputs (the columns
drive the widths: 40/56/56 px, the two key columns split the remainder,
112 px for the 10-digit counter). Ids and behaviour are unchanged (the
number span still toggles its red flag, the inputs keep their handlers).
Guards: html.test.js checks the keyset table headers and tbody;
cards_form.test.js checks the row markup. sw cache simple-v366.
Tests: 665 Python + 788 frontend green; the whole inline PWA script
syntax-checked.