NONE: Add basic frontend routing for the admin page

[Roystbeef]

Adding the basic routing/skeleton for the admin configuration page and the API calls it makes to make these decisions.

This is blocked on #112 for the /checkAuth route to succeed since it currently does not support the context-qsh but you can get around this locally for testing by applying the changes in #106

Screenshots

Skeleton page for logging in

Skeleton page for connecting a team

Skeleton page for rendering the connected teams

Test Plan

• Assert that when you haven't connected, you are shown the continue button
• Assert that after clicking continue, you are prompted to install the app
• Assert that upon success, when you go back to the original page, you are shown the connect a team placeholder
• Make a post request to connect a figma team for this connection id and refresh the configure page
• Assert that you are shown the connected teams placeholder now