use headers for preview and environment config

[mwickett]

🎟️ Asana Task

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Description

DatoCMS is shifting to use headers rather than URLs for specifying a content environment and draft/published content. This changes our platform-cms package to match.

PR Checklist 🚀

• Conduct thorough self-review.
• Add or update tests as appropriate.
• Write a useful description (above) to give reviewers appropriate context.
• Identify (in the description above) and document (add Asana tasks on this board) any technical debt that you're aware of, but are not addressing as part of this PR.

[changeset-bot]

🦋 Changeset detected

Latest commit: 632aeeb

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@hashicorp/platform-cms	Minor
@hashicorp/platform-cli	Patch

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[github-actions]

📦 Canary Packages Published

Latest commit: 632aeeb

Published 2 packages

@hashicorp/[email protected]

npm install @hashicorp/platform-cli@canary

@hashicorp/[email protected]

npm install @hashicorp/platform-cms@canary

[mwickett]

woof