Move group-level Cycle Analytics to the group sidebar

Problem

Currently, Cycle Analytics lives in two forms:

• Cycle Analytics in the Analytics Workspace (Premium/Silver), currently accessible in the Analytics area in the navigation topbar (https://gitlab.com/-/analytics/cycle_analytics, for example).
• Cycle Analytics for individual projects (Core), currently accessible in the "Project overview" section of the project sidebar.

As shared in #30079 (closed), this is confusing and having a Cycle Analytics feature live in the topbar causes challenges for our buyer model.

Proposal

• Remove Cycle Analytics from the navigation workspace.
• Add group-level Cycle Analytics to the "Group overview".

This should stay in Premium/Silver.