[BranchSelector] Update UI to make support happy

[lloydhumphreys]

• [x] Don't break existing functionality that if you have a lot of companies you just get a table view
• [x] Move search to the top of the page, because they always get confused that it's in the middle of the page (and their screens are small, so sometimes it's at the bottom!)
• [x] Remove the "Current Branch" section and instead make the first card in the list the "current branch" with a blue border or something to save space and see more on screen.
• [ ] Provide a way to start searching using the keyboard rather than clicking - see something like tailwindcss.com press / to focus

[DocGroth]

Forget the buttons in the header thats shown in the design, and add a log out ts-element button instead

[zdlm]

Sorry. Can't do that. the button is generated by tradeshift.ui API

[lloydhumphreys]

Done.