[Challenge] Create a `ChallengePlugin`

[Ishadijcks]

A challenge consists of

interface ChallengeDefinition {
  id: string;
  startConditions: Condition[];
  endConditions: Condition[];
  challengeModifiers: Bonus[];
  rewards: Output[];
  rewardBonuses: Bonus[];
  autocomplete?: bool;
}

Then you can start a challenge and the modifiers will apply while its running. On completion you get the rewards and the new bonuses are active.