fix(oxfmt): avoid embedded TSFN crash by returning errors as data (take2)

[leaysgur]

Fixes #19713 closes #19742

[leaysgur]

• fix(oxfmt): avoid embedded TSFN crash by returning errors as data (take2) #19806 👈 (View in Graphite)
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[Copilot]

Pull request overview

This PR fixes a critical crash in oxfmt related to ThreadsafeFunction (TSFN) cleanup in napi-rs. The fix addresses V8 fatal checks that occurred during teardown when error values were dropped in heavily concurrent runs. The solution changes embedded code formatters to return null on error instead of throwing exceptions, while keeping the file formatter's exception-throwing behavior intact.

Changes:

• Modified three embedded code formatters (formatEmbeddedCode, formatEmbeddedDoc, sortTailwindClasses) to return null on error instead of rejecting promises
• Updated Rust TSFN type definitions to use Promise<Option<T>> instead of Promise<T> for affected callbacks
• Updated TypeScript bindings and type annotations to reflect the new nullable return types

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

File	Description
apps/oxfmt/src/main_napi.rs	Updated TypeScript type annotations for embedded formatter callbacks to return string | null or string[] | null
apps/oxfmt/src/core/external_formatter.rs	Changed TSFN return types to Promise<Option<T>> and updated match arms to handle Ok(Some), Ok(None), and Err cases with explanatory comments
apps/oxfmt/src-js/cli/worker-proxy.ts	Changed embedded formatter functions to return null instead of throwing errors, with clear documentation explaining the TSFN crash issue
apps/oxfmt/src-js/bindings.d.ts	Updated TypeScript function signatures to reflect nullable return types for embedded formatters

[leaysgur]

@Boshen Instead of resolving the conflict for #19742, I essentially tried the same approach again.

Could you please verify this locally?