Derive WC node helm chart registry from registry_mirrors, decoupled from sylva_base_oci_registry

What does this MR do and why?

cluster.helm_oci_url.* (for the charts pulled by the helm-install-* jobs running on cluster nodes ) was derived from sylva_base_oci_registry, which is the registry used by the management cluster. This made it impossible to deploy a workload cluster whose nodes sit in a different network zone and cannot reach that registry.

Both registries are now derived independently from registry_mirrors.

sylva_base_oci_registry no longer automatically computed from the registry sylva-units itself was pulled from for OCI deployments. Deployments pulling sylva-units from a private registry must now either configure a registry_mirrors entry for registry.gitlab.com or set sylva_base_oci_registry explicitly.

This MR also adds _internal.sylva_base_oci_registry_derived_from_sylva_units_source so that users who want to set `sylva_base_oci_registry` based on the sylvaUnitsSource , can easily set it

Related reference(s)

closes #4381 (closed)

Test coverage

CI configuration

Below you can choose test deployment variants to run in this MR's CI.

Click to open to CI configuration

Legend:

Icon	Meaning	Available values
☁️	Infra Provider	capd, capo, capm3
🚀	Bootstrap Provider	kubeadm (alias kadm), rke2, okd, ck8s
🐧	Node OS	ubuntu, suse, na, leapmicro
🛠️	Deployment Options	Deployment option list and description
🎬	Pipeline Scenarios	Available scenario list and description
🟢	Enabled units	Any available units name, by default apply to management and workload cluster. Can be prefixed by mgmt: or wkld: to be applied only to a specific cluster type
🔴	Disabled units	Any available units name, by default apply to management and workload cluster. Can be prefixed by mgmt: or wkld: to be applied only to a specific cluster type
🏗️	Target platform	Can be used to select specific deployment environment Available platform list and description
⚡	Pipeline control	autorun, manual or blocking. Can be used to override global config and start a deployment pipeline the required way

• 🎬 preview ☁️ capd 🚀 kadm 🐧 ubuntu
• 🎬 preview ☁️ capo 🚀 rke2 🐧 suse
• 🎬 preview ☁️ capm3 🚀 rke2 🐧 ubuntu
• ☁️ capd 🚀 kadm 🛠️ light-deploy 🐧 ubuntu
• ☁️ capd 🚀 rke2 🛠️ light-deploy 🐧 suse
• ☁️ capo 🚀 rke2 🐧 suse
• ☁️ capo 🚀 rke2 🐧 leapmicro
• ☁️ capo 🚀 kadm 🐧 ubuntu
• ☁️ capo 🚀 kadm 🐧 ubuntu 🟢 neuvector,mgmt:harbor
• ☁️ capo 🚀 rke2 🎬 rolling-update 🛠️ ha 🐧 ubuntu
• ☁️ capo 🚀 kadm 🎬 wkld-k8s-upgrade 🐧 ubuntu
• ☁️ capo 🚀 rke2 🎬 rolling-update-no-wkld 🛠️ ha 🐧 suse
• ☁️ capo 🚀 rke2 🎬 sylva-upgrade 🛠️ ha 🐧 ubuntu
• ☁️ capo 🚀 rke2 🎬 sylva-upgrade-from-1.6.x 🛠️ ha,misc 🐧 ubuntu
• ☁️ capo 🚀 rke2 🛠️ ha,misc 🐧 ubuntu
• ☁️ capo 🚀 rke2 🛠️ misc 🐧 ubuntu 🟢 mgmt:harbor 🔴 neuvector
• ☁️ capo 🚀 rke2 🛠️ ha,misc,openbao 🐧 suse
• ☁️ capo 🚀 rke2 🐧 suse 🎬 upgrade-from-prev-tag
• ☁️ capm3 🚀 rke2 🐧 suse
• ☁️ capm3 🚀 kadm 🐧 ubuntu
• ☁️ capm3 🚀 ck8s 🐧 ubuntu
• ☁️ capm3 🚀 kadm 🎬 rolling-update-no-wkld 🛠️ ha,misc 🐧 ubuntu
• ☁️ capm3 🚀 rke2 🎬 wkld-k8s-upgrade 🛠️ ha 🐧 suse
• ☁️ capm3 🚀 kadm 🎬 rolling-update 🛠️ ha 🐧 ubuntu
• ☁️ capm3 🚀 rke2 🎬 upgrade-from-prev-release-branch 🛠️ ha 🐧 suse
• ☁️ capm3 🚀 rke2 🛠️ misc,ha 🐧 suse
• ☁️ capm3 🚀 rke2 🎬 sylva-upgrade 🛠️ ha,misc 🐧 suse
• ☁️ capm3 🚀 kadm 🎬 rolling-update 🛠️ ha 🐧 suse
• ☁️ capm3 🚀 ck8s 🎬 rolling-update 🛠️ ha 🐧 ubuntu
• ☁️ capm3 🚀 rke2|okd 🎬 no-update 🐧 ubuntu|na
• ☁️ capm3 🚀 rke2 🐧 suse 🎬 upgrade-from-release-1.5
• ☁️ capm3 🚀 rke2 🐧 suse 🎬 upgrade-to-main

Global config for deployment pipelines

• autorun pipelines

• allow failure on pipelines

• record sylvactl events

Notes:

• Enabling autorun will make deployment pipelines to be run automatically without human interaction
• Disabling allow failure will make deployment pipelines mandatory for pipeline success.
• if both autorun and allow failure are disabled, deployment pipelines will need manual triggering but will be blocking the pipeline

Be aware: after configuration change, pipeline is not triggered automatically. Please run it manually (by clicking the run pipeline button in Pipelines tab) or push new code.