Description

This PR includes some refactoring to the single-tab-processing feature, fixes to some issues which were introduced there and adds some relevant test coverage.

Relevant Technical Choices

• Used chrome.devtools.inspectedWindow.eval instead of chrome.tabs.query to get the site URL.
• Added a loader to the DevTools which fixes the flash of the Analyze the tab screen.

Testing Instructions

• Open the terminal and run npm I && npm run dev.
• Open any site and go to Privacy Sandbox in DevTools you should first see a loader for a brief period of time then see the cookies landing page.
• The problem of `First Party cookies not found should not persist for long anymore.