Add clusters Actions menu to group and admin views

What does this MR do and why?

Currently, we have different views for the project, group, and admin level clusters pages as we don't support Agent for the group and admin clusters yet.

This MR unifies views for all levels. It adds the Actions menu to the group and admin views. If the Agent is not supported for the current level, it shouldn't be shown as an option in Actions and as a tab in main view.

Screenshots or screen recordings

Group level:

Before	After

Admin level:

Before	After

How to set up and validate locally

Visit Kubernetes section under the Groups and Admin views.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #352720 (closed)