feat: Help Cog

[eluric]

Just adds a command that lets people see a list of commands. The commands listed are different based on if the user is an executive or not.

[eluric]

QOL changes:

• Puzzle ID is generated automatically when a new puzzle is created.
• Teams now receive an additional message upon completing each meta, informing them that the next set of puzzles is available
• Completion of the Metameta adds a victory role to the members which gives them access to a finisher's lounge
• Check mark next to solved puzzles when teams do /puzzle list

Minor changes:

• Team names cannot match the role name of the execs