Set the focus to the card that was clicked

As a busy product manager entering lots of items, I want cards I click on to become focused so that I can use keyboard shortcuts to quickly move into my next action, such as `Tab` to create a new card, `↵` to re-open the card, or `↑` to move focus to the previous card.

Given I have a story card under a step
When I click on the story card
Then the story card (in the map) becomes focused 
And the card opens in a modal

Given a story is open in a modal
When I close the modal
Then the story card remains focused
And I can use keyboard shortcuts in the context of the focused card