[Internal]: Re-design the "AI for Security" docs

[dhru42]

Description

What: Re-design the "AI for Security" docs "home page"
Why: The current page is too rigid and uninviting, and provides very little value except to re-direct to other sub-pages. We'd like to use this page to get users excited about our AI features, and how our users are benefiting them.
How: Add more visuals like images, walk-through videos/GIFs.

Resources

N/A

Which documentation set does this change impact?

Elastic On-Prem and Cloud (all)

Feature differences

N/A

What release is this request related to?

N/A

Serverless release

ASAP

Collaboration model

The documentation team

Point of contact.

Main contact: @dhru42

Stakeholders: @jamesspi