Parse description from gallery games

[recursiveforte]

We should have a function to parse code from any gallery game and return a description; usually the block of text within the first block comment, after the metadata.

Note from Graham: It would be nice if we settled on a structured way of defining the descriptions. We discussed this verbally, you mentioned there might be an issue w/ multiline support

[grymmy]

Note - this is a requirement for YSWS unified airtable from @zachlatta