Pages hub should show pages divided in categories

[rajat1saxena]

Currently, the /pages route shows all the page under one category. We need to show the pages under two categories:

1. Site pages: These pages cannot be deleted
2. Custom pages: Pages created by the user. These can be deleted.

Design

Look for "Pages hub" in https://www.figma.com/design/bYozbDhC68KL03aGuK7YSp/CourseLit?node-id=197-44&node-type=frame&t=4StCNzSrVpi6RT6o-0