Duo Agent platform sessions support multiple namespaces

What does this MR do and why?

Duo Agent platform sessions support multiple namespaces

In the near future, we will want to support adding the Automate menu under different namespace. Currently some of the data fetching was harcoded to project, so when we need to support group, users, admin, etc we will want it to be easily extensible.

References

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Make sure you have AI features enabled https://docs.gitlab.com/development/ai_features/
2. Turn on two feature flags: duo_workflow and duo_workflow_in_ci
3. Navigate to a project with AI features
4. On the left, you will see the Agents menu
5. Click on it, it will take you to fullpath/-/automate
6. This will load your workflows in that project
7. If you have none, notice the empty screen
8. If you need to populate flows, run the rake task for your project (ee/lib/tasks/gitlab/duo_workflow/duo_workflow.rake) bundle exec rake "gitlab:duo_workflow:populate[50,20,user@example.com,gitlab-org/gitlab-test]"
   1. The user here should be the logged in user for you to see them, and the project the one you will test in.
9. Navigate to the Automate => Agent sessions page
10. Click around all should work
11. Check the dev console, no errors!

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