Add duo sast VR enabled setting

What does this MR do and why?

Add duo sast VR enabled setting.

This is essentially the same as !212703 (merged) except this is just creating the setting in the database, models, API, etc. This does not yet implement the actual setting functionality of stopping the SAST VR from running.

References

Screenshots or screen recordings

Before	After

How to set up and validate locally

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Related to #580563