Implement the new marketplace page

[SherRao]

Description

This page is accessible to logged-in and logged-out users, and will display differently depending on the auth context AND permission context.

This page is well documented by the parent ticket and all the design sibling tickets - refer to them as well as the Figma for full context.

Checklist

Before submitting this ticket, make sure this ticket:

• Is labelled properly - if this is a refactor, add the label!
• Has the SPUR project assigned to it.
• Has an assigned milestone.

And lastly:

• Once someone picks up this ticket, make sure to assign it.