Zoom to and highlight active item on map

[reefdog]

When you've navigated to the resource detail page for a piece of artwork, we should zoom the map to that pin (we'll probably want to fine-tune the zoom level during development), and custom-format the pin (larger + #ffe16a?).

[hminsky2002]

@reefdog something I was wondering actually was did you have any thoughts on the map icons themselves? we theoretically could use any image we want, these are just the ones provided by leaflet. Conversely, they are perfectly serviceable. Just wanted to bring it up!

[reefdog]

Oh yeah, I'd love to do a design pass on the map itself. For now if we can at least add the zoom and highlight functionality more can wait — but I'll open a task!

[reefdog]

Delivered by #99 and #102.