add impacted area square for hazard map legend

[loganmcdonald-noaa]

What does this PR do? 🛠️

Finishes #1355 by adding the small legend square.

[github-actions]

This PR modifies theme Javascript or CSS assets but does not update the theme libraries file. Did you mean to update the appropriate version information in the libraries file?

[github-actions]

This PR modifies theme Javascript or CSS assets but does not update the theme libraries file. Did you mean to update the appropriate version information in the libraries file?

[eric-gade]

LGTM 👍

[partly-igor]

Colors and legend are looking great, the only issue I am noticing is that on mobile the map has gotten a little squished (see screenshots below). I am guessing that the legend is counting in the aspect-ratio calculation? We want the map itself to be 3:2 (width:height), in the PR it's closer to 2.2:1

PR

beta

[partly-igor]

It's looking really good, the only thing I noticed with the last update is that the map control floating/z-index issue was reverted because the isolation class was removed. After that I think 👍

Adding screenshot to capture what I mean

[partly-igor]

We'll want to move the wx-isolation-isolate class from here and put it on the wx-alert-map element