Stemmen tellen

Ballots that rank a few options (school trips, class pets), counted with one
method. The author gives the ballot profile once: the options, and each kind
of ballot with how many voters cast it. The plugin computes everything else:
the counts, the winner, the answer key and the worked computation in the
teacher manual. So the key can't be wrong, and a variant is a matter of
changing a count.

Pupils lay the ballots out on the table as rows of chips from the material
set, one colour per option (`chip`). The booklet prints the ballots as a
table: a row per kind of ballot, with its count and the options in order as
chips in their fixed colours, never the theme's. Set `showBallots: false` on
later tasks about the same vote and refer to the first one.

One task per `method`:

- `plurality`: the most 1st choices wins. The sheet has a number per option
  and the winner's bubbles.
- `runoff`: the option with the fewest votes drops out and its ballots go to
  their next choice that is still in, until one option has more than half
  the votes. The sheet has a row per round: a number per option (0 for an
  option that is out already) and a bubble to colour in for the option that
  drops out; the last round has a winner and no bubbles.
- `borda`: points per place (`points`, default n−1 down to 0). The booklet
  prints the points; the sheet has a number per option and the winner.
- `pairwise`: every two options in a duel: how many ballots rank each one
  higher. The sheet has the duels, two numbers each, and the winner, the
  option that wins every duel.

`ask: winner` leaves out the count and asks only for the winner.

Graded per region: each number is a point, and each row of bubbles (a
round's dropout, the winner) is a point when exactly the right bubble is
coloured in. Validation refuses rankings that don't list every option once,
two options with one chip colour, and ties that leave the answer open: two
options with the most votes or points, two with the fewest in a runoff round,
or no option that wins every duel. It says which options tie, so the author
can change a count.

The same profile can give different winners per method; that is the point of
the bundle. Keep the voters (the sum of the counts) at 20 or fewer when
pupils lay out every ballot: a set has 20 chips per colour.