[Spike] Investigate impacts of Helm 3.13+ upgrade

Summary

Working through #5424 we've uncovered ( see #5424 (comment 1853658175) ) potential issues with Helm upgrade as we've been heavily relying on patterns that are discontinued as of 3.13

Re-posted list from upstream

• Fixing precedence issue with the import of values. https://github.com/helm/helm/issues/12480
• Values precedence in helm 3.13.1 https://github.com/helm/helm/issues/12511
• Helm v3.13.0 and above breaks umbrella charts exposing empty values https://github.com/helm/helm/issues/12599
• Values precedence in Helm is an incompatibility mess! https://github.com/helm/helm/issues/12677
• Imported values doesn't override subchart values https://github.com/helm/helm/issues/12730
• Upgrde Helm to 3.14.0 or later (fixes issue in treatment of parent/child chart treatment) https://github.com/fluxcd/helm-controller/issues/878
• subchart keys can not be removed by parent chart in v3.13.* when --values (-f) flag is used https://github.com/helm/helm/issues/12488