Improve Area search functionality

[taylorbhogan]

• Change UI: default selection for location should be "select location" and USA should be included, but perhaps not even first.
• Implement more powerful API search function. load all results and send those to the store.
• the frontend will be exclusively responsible for pagination; all results will be loaded.
• add conditional note to loading screen: if location is USA, render a loading image with a note, something like "With ambition must come patience - thanks for hanging in there while we comb through all of the 4,000 public lands you can explore in the United States.