[Helm] Publish the chart to a public Helm repository

Problem The Helm chart at packages/twenty-docker/helm/twenty can only be installed by cloning the monorepo and pointing helm install at the local path. This causes a few practical issues for self-hosters: • The chart cannot be added with helm repo add, so it is left out of GitOps tools that rely on HelmRepository sources (Flux). The choice is either to fork and re-package the chart on your own infrastructure, or to fall back to manual helm install outside of GitOps, which breaks fleet uniformity. • Renovate and Dependabot cannot track new chart versions automatically, so version bumps depend on whoever is maintaining the local clone. • The Chart.yaml appVersion is not bumped on release. It currently points to v1.14.0 while the product is on v2.16.x, so anyone who does not override image.tag in their values.yaml ends up running a very outdated image without noticing. The community chart at AMecea/helm-twentycrm is the workaround some users take today. It is…