[Prototype only] Collection focus mode

[mcturco]

This PR is for design reference only

The final implementation plan should be engineering-led. This draft PR to show the changes in case it is helpful for implementing the final UI styling.

Prototype summary

• By default, users should now have a focus mode interaction when a request collection or any of its children is clicked
• A css animation makes the focus in and out transition smooth
• Contains inline renaming of the collection while in focus mode
• Shows where to add a setting to preferences for toggling this behavior on and off as preferred by the user