feat(ui): add namespace input to UserInfo page for SSO RBAC NS delegation. Fixes #12041

[MasonM]

Fixes #12041

Motivation

When using SSO RBAC Namespace Delegation, there's currently no way of seeing which service account maps to the user in a given namespace. This can be very confusing to a user who only has access to a specific namespace, since they have no way of knowing what permissions they have for that namespace.

Modifications

This updates the /api/v1/userinfo endpoint to support a ?namespace query parameter, which the SSO backend code already supports and will use to look up service account details when present: https://github.com/argoproj/argo-workflows/blob/7b2c4aa3e7290b186029d1b53eea1cb69166f7a0/server/auth/gatekeeper.go#L228-L237 https://github.com/argoproj/argo-workflows/blob/7b2c4aa3e7290b186029d1b53eea1cb69166f7a0/server/auth/gatekeeper.go#L305-L314

On the UI side, this adds a namespace input filter on the top of the page, and updates the UserInfo page to pass it when calling /api/v1/userinfo. Note that the namespace input is shown even if SSO RBAC NS delegation isn't enabled. The linked issue says "Only show this input box if SSO RBAC Namespace delegation is enabled", but there's no way of doing this modifying the /api/v1/info API, which has security ramifications per @agilgur5: https://github.com/argoproj/argo-workflows/issues/12041#issuecomment-2358743157

The only thing I wasn't quite sure about is error handling: if someone enters an invalid namespace, then /api/v1/userinfo will ignore it and silently fall back to the installation namespace, which could cause confusion. Ideally, the UI would detect that and show an informative error message, but that'd require non-trivial API changes.

https://github.com/user-attachments/assets/5109136a-221f-4173-80e2-1f12b662fd7f

Verification

Testing procedure:

1. Created the following manifest and ran kubectl apply -f on it:

   apiVersion: v1
   kind: Namespace
   metadata:
     name: delegation-test
   ---
   apiVersion: v1
   kind: ServiceAccount
   metadata:
     name: delegated-sa
     namespace: delegation-test
     annotations:
       workflows.argoproj.io/rbac-rule: "true"
       workflows.argoproj.io/rbac-rule-precedence: "2"
   ---
   apiVersion: v1
   kind: Secret
   metadata:
     name: delegated-sa.service-account-token
     namespace: delegation-test
     annotations:
       kubernetes.io/service-account.name: delegated-sa
   type: kubernetes.io/service-account-token
   data:
     ca.crt: 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
     namespace: ZGVsZWdhdGlvbi10ZXN0Cg==
     token: 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
   

   I thought about creating a new profile under test/e2e/manifests/sso-delegated with these manifests that could be used to test this via make start PROFILE=sso-delegated, but I don't know if that's worth it.
2. Run make start UI=true PROFILE=sso SSO_DELEGATE_RBAC_TO_NAMESPACE=true NAMESPACED=false
3. Visit http://localhost:8080/
4. Click "Login"
5. Click "Log in with Example"
6. Click "Grant Access"
7. Click the icon for the UserInfo page on the left navigation bar
8. Verify namespace input is populated with the installation namespace

See the above recording for the results. Also, I verified the namespace input is replaced with fixed text when using managed namespaces: