docs: Bump self-managed to v26.0.0-rc.4

for preview only, but we should merge this with proper version when v26.0.0 gets cut

Author: def-

doc/user/data/self_managed/latest_versions.yml

@@ -1,7 +1,7 @@
-terraform_gcp_version: v0.5.10
-terraform_azure_version: v0.5.10
-terraform_aws_version: v0.5.10
-terraform_helm_version: v0.1.31
-operator_helm_chart_version: v25.2.15
-orchestratord_version: v0.164.1
-environmentd_version: v0.147.20
+terraform_gcp_version: v0.6.1
+terraform_azure_version: v0.6.1
+terraform_aws_version: v0.6.1
+terraform_helm_version: v0.1.32
+operator_helm_chart_version: v26.0.0-rc.4
+orchestratord_version: v26.0.0-rc.4
+environmentd_version: v26.0.0-rc.4

doc/user/layouts/shortcodes/self-managed/versions/curl-sample-files-local-install.html

@@ -2,10 +2,9 @@
 {{ $environmentd_version := site.Data.self_managed.latest_versions.environmentd_version }}
 
 ```shell
-mz_operator_version=self-managed-{{ $operator_helm_chart_version}}
 mz_version={{ $environmentd_version }}
 
-curl -o sample-values.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_operator_version/misc/helm-charts/operator/values.yaml
+curl -o sample-values.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_version/misc/helm-charts/operator/values.yaml
 curl -o sample-postgres.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_version/misc/helm-charts/testing/postgres.yaml
 curl -o sample-minio.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_version/misc/helm-charts/testing/minio.yaml
 curl -o sample-materialize.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_version/misc/helm-charts/testing/materialize.yaml

doc/user/layouts/shortcodes/self-managed/versions/upgrade/upgrade-steps-local-kind.html

@@ -18,9 +18,9 @@
 1. Get the sample configuration files for the new version.
 
    ```shell
-   mz_operator_version=self-managed-{{ $operator_version }}
+   mz_version={{ $environmentd_version }}
 
-   curl -o upgrade-values.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_operator_version/misc/helm-charts/operator/values.yaml
+   curl -o upgrade-values.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_version/misc/helm-charts/operator/values.yaml
    ```
 
    If you have previously modified the `sample-values.yaml` file for your

doc/user/layouts/shortcodes/self-managed/versions/upgrade/upgrade-steps-local-minikube.html

@@ -18,9 +18,9 @@
 1. Get the sample configuration files for the new version.
 
    ```shell
-   mz_operator_version=self-managed-{{ $operator_version }}
+   mz_version={{ $environmentd_version }}
 
-   curl -o upgrade-values.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_operator_version/misc/helm-charts/operator/values.yaml
+   curl -o upgrade-values.yaml https://raw.githubusercontent.com/MaterializeInc/materialize/refs/tags/$mz_version/misc/helm-charts/operator/values.yaml
    ```
 
    If you have previously modified the `sample-values.yaml` file for your