Backport of Update "Disaster recovery for WAN-federated datacenters" into release/1.21.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #22834 to be assessed for backporting due to the inclusion of the label backport/1.21.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
you will see a blank no-op commit below. If at least one commit succeeded, you
will see the cherry-picked commits up to, not including, the commit where
the merge conflict occurred.

The person who merged in the original PR is:
@danielehc
This person should resolve the merge-conflict(s) by either:

• Manually completing the cherry picks into this branch
• Creating a new branch and manually cherry-picking all commits being backported

merge conflict error: POST https://api.github.com/repos/hashicorp/consul/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Description

Update "Disaster recovery for WAN-federated datacenters" https://hashicorp.atlassian.net/browse/CE-921

This started as a simple update of the content of a single page but, it became a full restructure of the whole manage/disaster-recovery content trying to rationalize the content and remove duplicated steps or concepts.

Preview

https://consul-git-CE-921-hashicorp.vercel.app/consul/docs/manage/disaster-recovery

Conflicts

This content supersedes the one in #22756 that, in my opinion should be closed.

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Overview of commits

• 83b9c2b

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR

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