Optionally strip cf-ew-raw prefix

[penalosa]

What this PR solves / how to test

Part of https://jira.cfdata.org/browse/DEVX-1312

When sending raw HTTP requests to the playground & quick edit, we'd previously been passing along the headers that the user specified directly in the request to the proxy. This meant that some headers were instead being interpreted by the browser/proxy rather than being passed along to the user-worker (e.g. Accept). This change supports optionally prefixing headers with cf-ew-raw-, which will be stripped before being passed to the user worker. Followup PRs will add this prefixing to the playground & quick edit UI to take advantage.

Author has addressed the following

• Tests
  • TODO (before merge)
  • Included
  • Not necessary because:
• E2E Tests CI Job required? (Use "e2e" label or ask maintainer to run separately)
  • I don't know
  • Required / Maybe required
  • Not required because: Doesn't touch Wrangler code
• Changeset (Changeset guidelines)
  • TODO (before merge)
  • Included
  • Not necessary because:
• Public documentation
  • TODO (before merge)
  • Cloudflare docs PR(s):
  • Not necessary because: Not currently documented

[changeset-bot]

🦋 Changeset detected

Latest commit: 0c50859

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

This PR includes changesets to release 2 packages

Name	Type
edge-preview-authenticated-proxy	Minor
playground-preview-worker	Minor

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-wrangler-6458

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/6458/npm-package-wrangler-6458

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-wrangler-6458 dev path/to/script.js

Additional artifacts:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-create-cloudflare-6458 --no-auto-update

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-cloudflare-kv-asset-handler-6458

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-miniflare-6458

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-cloudflare-pages-shared-6458

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-cloudflare-vitest-pool-workers-6458

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/10320454789/npm-package-cloudflare-workers-shared-6458

Note that these links will no longer work once the GitHub Actions artifact expires.

---

wrangler@3.70.0 includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20240806.0
workerd	1.20240806.0	1.20240806.0
workerd --version	1.20240806.0	2024-08-06

Please ensure constraints are pinned, and miniflare/workerd minor versions match.