[Lost at Sea Task] Add game instructions, context, and info icon reference

[cjqian]

Before users start on the initial task, provide the game instructions (appendix of https://docs.google.com/document/d/11IJXf-tZVKZp592-MNM3hIj9Rft6cBYV7UcYFS9VJJc); either in a separate panel or as a pop-up.

This information should be accessible (e.g. as an information icon?) for users to reference throughout the tasks.