Add support for model armor both on cloud run single and cloud run rag

[LucaPrete]

I would add this when it's available as a service extension of load balancers

[LucaPrete]

This should also be integrated with cloud run rag search now

[aurelienlegrand]

Did some tests and the global Model Armor endpoint doesn't support all methods (yet) and the regional Model Armor endpoint must be called from the same region, thus impacting where the rest of the solution must be deployed.
I think we should wait a bit more for support to be more mature.

[LucaPrete]

I'm fine with it. Thanks for spending time and looking into this!

[LucaPrete]

@aurelienlegrand can I ask you a favor? Any chance we can keep a PR open just to keep track of the code needed please?
Let's put in front of the description [WIP] so it's clear it's not ready to be merged any time soon

[aurelienlegrand]

PR is here: #45

I ran into another issue: Cloud Armor + Model armor cannot be enabled on the same backend service: https://cloud.google.com/service-extensions/docs/callouts-overview#other_limitations. I will investigate to see if this will be lifted in the future.

[LucaPrete]

Update: we suspended the activity as Model Armor right now supports only OpenAI models.
When other models and formats will be supported will complete the integration.

[LucaPrete]

Update: we should be back in business. Model Armor should now be integrated to LBs and should support Gemini.