fix: remove JsonResponse from server function response

[schiller-manuel]

Summary by CodeRabbit

• Refactor
  • Fetchers now return the raw awaited response directly instead of a wrapped response type.
  • Removed an obsolete public response-type alias from the API surface.
  • Consumers that relied on the removed wrapper may need small type adjustments.

[coderabbitai]

Walkthrough

Updated TypeScript typings in packages/start-client-core: fetcher call signatures now return Promise<Awaited> and the public FetcherData<TResponse> type was removed; exports adjusted accordingly.

Changes

Cohort / File(s)	Summary
Fetcher type updates packages/start-client-core/src/createServerFn.ts, packages/start-client-core/src/index.tsx	Changed OptionalFetcher and RequiredFetcher call signatures to return Promise<Awaited<TResponse>> and removed the exported FetcherData<TResponse> type; removed FetcherData from re-exports in index.tsx.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• fix: register createServerFn fetcher as serializable #5268 — Modifies createServerFn fetcher typings and touches the same Fetcher/FetcherBase surface.
• fix: raw response handling #5276 — Also changes fetcher/FetcherData typings and re-exports in start-client-core.

Suggested reviewers

• chorobin

Poem

A rabbit nudged the types today,
Swapped wrappers for a clearer way.
Promises hop to their true form,
Removed the extras, trimmed the norm.
Hooray — the code can now leap, light and gay. 🐇✨

Pre-merge checks and finishing touches

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The title clearly and concisely describes the core change of removing the JsonResponse type from the server function response without extraneous detail, making it immediately understandable to reviewers scanning the history.
Docstring Coverage	✅ Passed	No functions found in the changes. Docstring coverage check skipped.

✨ Finishing touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch serverfn-no-json

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📜 Recent review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 998aa29 and a54b72e.

📒 Files selected for processing (2)

• packages/start-client-core/src/createServerFn.ts (1 hunks)
• packages/start-client-core/src/index.tsx (0 hunks)

💤 Files with no reviewable changes (1)

• packages/start-client-core/src/index.tsx

🚧 Files skipped from review as they are similar to previous changes (1)

• packages/start-client-core/src/createServerFn.ts

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• GitHub Check: Test

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View your CI Pipeline Execution ↗ for commit a54b72e

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---

☁️ Nx Cloud last updated this comment at 2025-10-02 17:06:56 UTC

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commit: a54b72e