We need some sort of sidebar on the left that allows a user to switch between different views/components.
- The sidebar should look similar to the VS Code sidebar.
- When hovering over an icon, a tooltip with a name should appear.
- It would be great if the icons can also be reordered via drag and drop (don't store the state persistent yet on page reload, we need to finish implementing the state management first)
For now, just add a sidebar item for each page (./repl, /blocks, ...) with a matching icon from lucide.

We need some sort of sidebar on the left that allows a user to switch between different views/components.
For now, just add a sidebar item for each page (./repl, /blocks, ...) with a matching icon from lucide.