test: restore docs proxy type-check

[mblode]

Summary

• type the docs proxy fetch spy as the platform fetch function
• preserve the RequestInit tuple type when asserting forwarded router headers
• add the repository-required empty Changeset

Why

TypeScript 7 inferred the zero-argument mock as [], so reading the second recorded call argument failed type-check even though the test passes at runtime.

Validation

• npm run check-types
• npm run test (82 passed, 1 skipped)
• npm run lint
• npm run build
• npx changeset status --since origin/main
• git diff --check

---

Note

Low Risk
Test-only typing fix and an empty changeset; no runtime or production behavior changes.

Overview
Fixes TypeScript 7 type-check failures in the docs proxy test that asserts Next.js router headers are forwarded to upstream fetch.

The fetch spy is now typed as vi.fn<typeof fetch>(...) so mock.calls[0][1] is treated as RequestInit and accessing headers type-checks. Adds the required empty Changeset file.

^{Reviewed by Cursor Bugbot for commit 5457c42. Bugbot is set up for automated code reviews on this repo. Configure here.}

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Project	Deployment	Actions	Updated (UTC)
diffhub-web	Ready	Preview	Aug 14, 2026 9:50pm

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