Add view all tab to the clusters page

What does this MR do and why?

This MR adds a view with both agents and clusters available to the Kubernetes section.

Current MR summaries changes to the Kubernetes section UX will be delivered in the following steps:

1. Move clusters_empty_state component to Vue --> !73064 (merged)
2. Change the navigation for the clusters base page --> !73163 (merged)
3. Change the copy and empty state illustrations in the existing components --> !73586 (merged)
4. Change the navigation on the clusters page to Vue and actions button on the top of the page (introducing the clusters_main_view and clusters_actions components --> !73637 (merged)
5. Add the 'All' tab <-- \textcolor{#FC6D26}{\textsf{You are here}}
6. Add an empty state variant for the Install new Agent modal --> !73636 (merged)

Adding a new view to show both Agent and Certificate based integrations as cards in the first tab. It shows up to 6 integrations in each card or the empty state.

• Agent tab should have the Recommended badge showing the tooltip on hover with some info and link to the docs.
• In case there are no connected agents it should show the Install new Agent button that opens the popup for the Agent creation UI
• Otherwise, there should appear a link to the agents' tab saying View all %{number} Agent based integrations. The number of the integrations should be shown here only if it's more than 6.
• In case there are no clusters connected via certificate it should show the button Connect existing cluster that navigates to the /clusters/new?tab=add view
• Otherwise, there should appear a link to the clusters' tab saying View all %{number} Certificate based integrations with the same logic as for the agents' card

More information is in the main MR(!71482 (closed))

Screenshots or screen recordings

• With both empty states

• With one empty state

• With less than 6 integrations

• With more than 6 integratinos

Recommended badge:

How to set up and validate locally

1. Visit the Infrastructure -> Kubernetes clusters section
2. To add content to the view follow these guides:
   • for Agents
   • for Certificate based integrations

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 #340759 (closed)