docs: add OEP-45/decision-0003

[gabor-boros]

This PR updates OEP-45 and adds a new, decision 0003 to give recommendation on large Open edX deployments.

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[felipemontoya]

In decision 2, the framing is:

For , the community maintains , and will make it compatible with

For Open edX operators who wish to deploy Open edX on Kubernetes, community-maintained Terraform modules and Helm Charts will be used to simplify the process of provisioning a Kubernetes cluster capable of loading one or more Open edX instances.

Building on top of the decision 0001, individual instances will be configured by Tutor and the Tutor plugin ecosystem

I like that framing better than to offer a straight up recommendation. Part of the appeal of OpenedX is the chameleon approach.

How do you feel about using something like:

A coalition of commercial providers maintains the Terraform modules and Helm chart described in decision 0002, as well as a growing ecosystem of open-source deployment tools. For operators deploying Open edX on Kubernetes, these resources (Drydock, Picasso, ArgoCD, Argo Workflows and GitHub Actions) provide flexible reference architectures.
We recognize that Open edX deployments vary widely in scale and infrastructure. Operators are free to blend these community tools with their own existing stack, and we encourage providers to share new deployment code, modules, or templates with the community.

Because Open edX intentionally supports diverse infrastructure needs, none of these tools are mandatory. Instead, the community focuses its efforts on ensuring these reference implementations and provider templates like OpenCraft's Launchpad, are maintained well enough to serve as reliable blueprints.

[felipemontoya]

We could add an introductory session, that explains these consequences and recommendations apply to those that decide to take the joint path of harmony+tools(argo, drydock,...)