Ordered punch-list (aiming to complete by 2021-01-08)
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-• Add "meta" as a checkbox field on puzzle creation/edit
-
-• Tweak /hunt and /round to treat meta puzzles as special (sort them
- first and add some META label)
-
-• Make `/puzzle` for a meta puzzle also display the names/answers of
- all puzzles in the round.
-
• Add /tag to add/remove tags (will force to all caps and store as a
prefix as part of the state string for now)