Resource recommendations

[alan-fang]

Is your feature request related to a problem? Please describe.
When volunteers do a search on the map view, and click on a resource they likely display high intent — for example, chances are that if they click on a tattoo removal resource, they will want resources similar to tattoo removal.

But what if the resource they clicked on doesn't quite fit the criteria they were looking for? We want to help them find similar resources that may also fit their search needs! There isn't a clear cut solution to identify all of a user's search needs, but if we show related resources our chances of giving them the right resource is much higher.

Describe the solution you'd like
Let's implement a (basic) recommendation system. Couple of ideas that this could entail: resources that have similar tags, within a specific radius, resources that may share part of a name, etc.

I'm keeping this fairly open-ended; this is a good opportunity to run with your implementation as you see fit and to work with design on bringing the feature to life!

Additional context
@eckels on design/pm