chore(registry): Add cloud engine endpoints module

[pietrodimarco-dfinity]

This pull request introduces a new module for Cloud Engine endpoints in the Registry Canister, owned by the DRE team.
The endpoints in this module support the ongoing development of the Engine control panel backend.
In particular, they enable automatic subnet creation, updates, and deletion for requests originating from a predefined Node Operator.
More about Cloud Engines POC here

[github-actions]

This pull request changes code owned by the Governance team. Therefore, make sure that
you have considered the following (for Governance-owned code):

1. Update unreleased_changelog.md (if there are behavior changes, even if they are
   non-breaking).

2. Are there BREAKING changes?

3. Is a data migration needed?

4. Security review?

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5. In the text entry box, respond to each of the numbered items in the previous
   section, declare one of the following:

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Brief Guide to "Externally Visible" Changes

"Externally visible behavior change" is very often due to some NEW canister API.

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If these changes are breaking, make sure that clients know how to migrate, how to
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Reference(s)

For a more comprehensive checklist, see here.

GOVERNANCE_CHECKLIST_REMINDER_DEDUP

No canister behavior changes