feat: consolidate Helm chart distribution to OCI-only and drop GitHub Pages

[udsmicrosoft]

Closes #326.

Summary

Removes the GitHub Pages-based Helm repository (https://documentdb.github.io/documentdb-kubernetes-operator) and consolidates Helm chart distribution to the OCI registry already published to GHCR (oci://ghcr.io/documentdb/documentdb-operator). Updates every workflow, action, script, and doc that still consumed the chart from GH Pages.

Changes

Release pipeline (no more GH Pages publish)

• Deleted .github/workflows/repair_helm_pages_release.yml (the 300+ line reusable workflow that rebuilt index.yaml and committed it to the gh-pages branch).
• Removed the publish-helm-pages job from release_operator.yml and from the deprecated release_images.yml. OCI publication via helm push is unchanged.

CI consumers migrated to OCI

• .github/actions/setup-test-environment/action.yml: the released-chart-version install path now runs helm install … oci://ghcr.io/documentdb/documentdb-operator --version <X>.
• .github/workflows/test-upgrade-and-rollback.yml: dropped helm repo add documentdb / helm repo update.
• "latest" version resolution: OCI registries don't support helm search repo, so both call sites now resolve latest by listing GHCR tags directly (`/v2/.../tags/list`) and picking the highest stable SemVer. This better matches the prior helm search repo … | .[0].version semantics than gh api releases/latest would (verified: 0.1.3 is present in GHCR but not in GitHub Releases).

Playground scripts

• documentdb-playground/aws-setup/scripts/create-cluster.sh: collapsed the "try GH Pages → fall back to OCI" structure into a single OCI install. GITHUB_USERNAME/GITHUB_TOKEN are now optional (GHCR public charts pull anonymously).
• documentdb-playground/aks-fleet-deployment/install-documentdb-operator.sh: replaced GH Pages install with OCI; requires explicit `CHART_VERSION` env var when not building a local chart (OCI has no implicit "latest").

Docs

• All install/quickstart/upgrade snippets switched to:
  ```bash
  DOCUMENTDB_VERSION=<x.y.z>
  helm install documentdb-operator oci://ghcr.io/documentdb/documentdb-operator \
  --version ${DOCUMENTDB_VERSION} \
  --namespace documentdb-operator --create-namespace --wait
  ```
• Files updated: index.md, getting-started/quickstart-kind.md, getting-started/quickstart-k3s.md, getting-started/deploy-on-eks.md, multi-region-deployment/setup.md, operations/upgrades.md, faq.md, documentdb-playground/aws-setup/README.md.
• operations/upgrades.md was restructured: `Step 1` now sets `TARGET_VERSION` and points users to GitHub Releases for available versions (replacing the now-impossible `helm repo update` / `helm search repo --versions` flow). The `Step 4` upgrade command and `--atomic` tip use the OCI URL.
• Stale `documentdb.github.io/...` link in `aws-setup/README.md` repointed to `documentdb.io/...`.

Root README

• New `📦 Install` section between `📚 Documentation` and `🚀 Quick Start`, with a copy-paste OCI install snippet, version-pinning guidance, link to GitHub Releases for version discovery, and the Helm 3.8+ requirement (per the issue's explicit ask about README discoverability to compensate for the loss of `helm search repo`).

Tradeoffs (per the issue)

• Users lose `helm repo add` + `helm search repo` discoverability — must consult GitHub Releases for available versions.
• Requires Helm 3.8+ (March 2022) for OCI support — already widely adopted.
• Significantly simpler release pipeline; no more `gh-pages` Helm-repo branch maintenance or `index.yaml` repair workflow.

Validation

• `yaml.safe_load` parses all modified workflows / composite action.
• `bash -n` parses both modified shell scripts.
• Final `grep` sweep for `helm repo add documentdb`, `documentdb.github.io/documentdb-kubernetes-operator`, `helm search repo documentdb`, `helm repo update documentdb`, `repair_helm_pages`, `publish-helm-pages` returns zero hits across the repo.
• Smoke-tested the GHCR tag-list resolver locally — returns `0.2.0` (matches what `helm search repo` would have returned against the old gh-pages index).
• Confirmed `oci://ghcr.io/documentdb/documentdb-operator` is anonymously pullable via the GHCR token endpoint, so the doc snippets work without `helm registry login`.

Out of scope (intentionally untouched)

• The `gh-pages` branch used by `deploy_docs.yml` for mike-based docs hosting is left alone — it serves a different purpose than the deprecated Helm repository and is not what issue Consider consolidating Helm chart distribution to OCI-only (drop GitHub Pages) #326 targets.

[documentdb-triage-tool]

🤖 Auto-triaged by documentdb-triage-tool.

Applied: documentation, CI/CD, ecosystem, enhancement
Project fields suggested: Component docs · Priority P2 · Effort L · Status In Progress
Confidence: 0.82 (mixed)

Reasoning

component from path globs (docs, ci, playground); effort from diff stats (147+516 LOC, 16 files); LLM: Cross-cutting consolidation of Helm chart distribution from GitHub Pages to OCI-only, touching release pipelines, CI workflows, playground scripts, and docs across multiple files and components.

If a label is wrong, remove it manually and ping @patty-chow so the rules can be tuned. The bot will not re-label items that already have component labels.

[Copilot]

Pull request overview

This PR removes the GitHub Pages–hosted Helm repository and standardizes Helm chart consumption and publication on the GHCR OCI registry (oci://ghcr.io/documentdb/documentdb-operator) across CI, docs, and playground scripts.

Changes:

• Removed the GitHub Pages Helm repo publishing workflow and its usage from release workflows.
• Migrated CI and scripts from helm repo add/search flows to OCI installs, including “latest” resolution via GHCR tag listing.
• Updated documentation and READMEs to use OCI-based install/upgrade commands and updated links.

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
documentdb-playground/aws-setup/scripts/create-cluster.sh	Simplifies operator install to OCI-only with optional GHCR auth.
documentdb-playground/aws-setup/README.md	Updates documentation link from GitHub Pages to documentdb.io.
documentdb-playground/aks-fleet-deployment/install-documentdb-operator.sh	Switches install flow from Helm repo to OCI and requires explicit version pinning.
docs/operator-public-documentation/preview/operations/upgrades.md	Reworks upgrade steps to remove Helm repo semantics and use OCI + version pinning.
docs/operator-public-documentation/preview/multi-region-deployment/setup.md	Updates multi-cluster install snippet to OCI-based Helm install.
docs/operator-public-documentation/preview/index.md	Updates primary install snippet to OCI-based Helm install with pinned version.
docs/operator-public-documentation/preview/getting-started/quickstart-kind.md	Updates quickstart install snippet to OCI.
docs/operator-public-documentation/preview/getting-started/quickstart-k3s.md	Updates quickstart install snippet to OCI.
docs/operator-public-documentation/preview/getting-started/deploy-on-eks.md	Replaces Helm repo setup docs/snippets with OCI distribution guidance.
docs/operator-public-documentation/preview/faq.md	Updates operator upgrade snippet to OCI + version pinning.
README.md	Adds an “Install” section documenting OCI installs and Helm version requirement.
.github/workflows/test-upgrade-and-rollback.yml	Removes Helm repo usage and resolves “latest” via GHCR tags.
.github/workflows/repair_helm_pages_release.yml	Deleted: removes GH Pages Helm repo repair/republish workflow.
.github/workflows/release_operator.yml	Removes GH Pages Helm publish job from operator release flow.
.github/workflows/release_images.yml	Removes GH Pages Helm publish job from deprecated images release flow.
.github/actions/setup-test-environment/action.yml	Updates released-chart install path to OCI and adds GHCR tag-based “latest” resolver.