[WIP] Chore (UI): Resizable component

[sprocketc]

The goal here is to replace our custom resizable panels with https://ui.shadcn.com/docs/components/resizable

A few notes about this

• The shadcn component is based on react-resizable-panels
• It doesn't support pixels, so we might have to use a workaround for the left sidebar (setting a css min-width in pixels kind of works)
• It uses localStorage to persist layouts by default. Although we can maintain the current persisting functionality, there is no reason to do that (see next point)
• We cannot set the width reactively. There is only an imperative API currently exposed
• The auto-collapsible panels cannot be combined with conditional panels (the collapsed panel is part of the dom but its width or height is zero), and conditional panels are required in our case because of the previous point, if we also want to avoid maintaining and passing around a reference of each panel