[codespace] backstage/keycloak login in codespace

[jkleinlercher]

new values file like https://github.com/suxess-it/sx-cnp-oss/blob/main/platform-apps/charts/backstage/values-k3d.yaml with codespace URLs

change https://github.com/suxess-it/sx-cnp-oss/blob/255cd1a15f61281eeddc55ab11ab9073f6c108b5/platform-apps/charts/backstage/values-k3d.yaml#L139

and all other backstage occurences for CORS

---

new clientId in https://github.com/suxess-it/sx-cnp-oss/blob/255cd1a15f61281eeddc55ab11ab9073f6c108b5/platform-apps/charts/backstage/values-k3d.yaml#L140 referencing to a new clientid created via a new resource similar to https://github.com/suxess-it/sx-cnp-oss/blob/255cd1a15f61281eeddc55ab11ab9073f6c108b5/platform-apps/charts/keycloak/templates/cp-keycloak-backstage-client.yaml#L11-L38 with kubectl apply

with a valid redirect url https://github.com/suxess-it/sx-cnp-oss/blob/255cd1a15f61281eeddc55ab11ab9073f6c108b5/platform-apps/charts/keycloak/templates/cp-keycloak-backstage-client.yaml#L31 corresponding to the codespace URL.

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additional realm similar to https://github.com/suxess-it/sx-cnp-oss/blob/main/platform-apps/charts/keycloak/templates/cp-keycloak-realm.yaml via kubectl apply

change realm name in https://github.com/suxess-it/sx-cnp-oss/blob/255cd1a15f61281eeddc55ab11ab9073f6c108b5/platform-apps/charts/backstage/values-k3d.yaml#L138

---

add forwardPort for keycloak in portal codespace

[jkleinlercher]

with https://github.com/suxess-it/sx-cnp-oss/pull/666 we added demouser1 in an entity, because importing from keycloak doesn't work at the moment: