feat: llm engine driver

[sozercan]

What this PR does / why we need it:

This is a fun new experimental engine we were discussing in the community call. requires open-policy-agent/frameworks#411 to merged in first.

see https://github.com/sozercan/gatekeeper/tree/llm/demo/llm for more information

demo: https://asciinema.org/a/QTBEBp8l0vE5wgD9yGgxE3mnV

possible future work is function calling/tool usage to query k8s api for referrential policies and ability to query external data sources.

Which issue(s) this PR fixes (optional, using fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when the PR gets merged):
Fixes #

Special notes for your reviewer:

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[JaydipGabani]

not stale

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[JaydipGabani]

not stale

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[JaydipGabani]

not stale

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.