Is your feature request related to a problem? Please describe.
This Helm chart has numerous places where you can enter sensitive credentials as a Helm value override. This breaks the basic security model of GitOps, making this chart only suitable for use with a literal "helm install", and even then, object last modified annotations will contain the plain text secrets in them. This is operationally unsafe and a compliance nightmare for any organization.

Describe the solution you'd like
Every single Helm value with the word "secret" in it gets an equivalent "existingSecret" key where you can specify subkey "name" and subkey "key", mapping to the name of the secret and the name of the key inside that secret, respectively.

Describe alternatives you've considered
I reviewed your helm template for OIDC configuration and it does not permit any other value to be specified other than the client secret.

Additional context
This is a very good and useful Helm chart but this is a critical step for operational security in GitOps environments.