🔨 refactor(PageComponent): add type prefix to new node IDs

🔨 refactor(ExtraSidebarComponent): remove Separator component
The PageComponent now generates new node IDs with a prefix that matches the type of the node. This improves the readability of the IDs and makes it easier to identify the type of node by looking at its ID. The ExtraSidebarComponent no longer uses the Separator component, as it is no longer needed.