add authentik-outpost helm chart

[andrycorr]

No description provided.

[shcherbak]

Thank You for your contribution!
I rendered the chart locally to confirm (helm template test . -f values.yaml, release name test):

• Service name -> test-authentik-outpost
• Ingress backend -> authentik-outpost
  Suggested fix: use {{ include "authentik-outpost.fullname" . }} for both the Ingress name and the backend service.name, consistent with deployment.yaml/service.yaml/secret.yaml.