Fixes

• Build contest tour: a player is no longer left falling or hurt after the tour sends them home. They stay protected until they stand on something again (30 seconds at most; flying counts), and a return that is refused, fails or leads into a world that is not loaded is tried again every 5 seconds for a minute while they stay protected (not while they ride something they mounted meanwhile), then on their next join. Anything riding on a player is set down before every teleport, a visit that is refused is told and the tour goes on, and a player on the death screen is skipped instead of being told another plugin refused the visit.
• A challenge that fails to start or to stop no longer blocks the round: it is cancelled and freed at once, the others keep running, and the next challenge can be drawn.
• A player who has just left the server is no longer drawn into a challenge.
• Hot potato: the first holder is announced once, the end of one round no longer takes the potatoes of another round from players, and a marked potato lying on the ground is removed when a player touches it.
• Luck: a wheel of fortune left with one spinner says so in its result line, and a mystery box whose taker left is no longer shown as untouched.
• Votes: a vote cast after the clock has run out no longer counts.
• challenges.yml after an update: a .catalogue-version file that holds no version is reported on each start and /prost reload, and nothing is added until it is fixed or deleted, and when the new challenges cannot be appended the log now says why (the file would not read any more, one of your entries would change, or the number of entries would change).