Juror Scoring: shift the levels by 1

[jaybuidl]

We want the jurors to start at level 1 instead of starting at level 0.
If they perform badly, we want them to drop progressively to level 0.

We need to tweak the score formula and check that

• The range boundaries are correct according Juror coherence score and level computation #888
• The score should remain fairly distributed among the jurors

Score levels:

[
  { scoreRange: [0, 20], level: 0, title: "Diogenes" },
  { scoreRange: [20, 40], level: 1, title: "Pythagoras" },
  { scoreRange: [40, 60], level: 2, title: "Socrates" },
  { scoreRange: [60, 80], level: 3, title: "Plato" },
  { scoreRange: [80, 100], level: 4, title: "Aristotle" },
];

[kemuru]

fixed on #1702