fix(grit): correct arrow_function slot indices for GritQL patterns

[TheBaconWizard]

AI disclosure

I used cursor agent and ai to explain how plugins get ran and how plugin tree sitter bindings work.

Summary

Add missing parameters argument to arrow_function tree-sitter mapping.

Motivation

I ran into this issue while trying to write my own plugins.

Test Plan

Added test + snapshot files.

I also performed the following test

$ biome search 'arrow_function(parameters=$parameters, body=$body)' ./scratch.ts

scratch.ts:1:11 search
  1 │ const a = () => {};
scratch.ts:2:13 search 
  2 │ const add = (a: number, b: number, c: number, d: number) => a + b + c + d;
scratch.ts:3:14 search 
  3 │ const add1 = (a: number, b: number) => a + b

(pointed at build binary)

and received expected output vs

$ npx @biomejs/biome search 'arrow_function(parameters=$parameters, body=$body)' ./scratch.ts

  ✖ Error executing the Grit query

[changeset-bot]

🦋 Changeset detected

Latest commit: 4fb6c61

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

This PR includes changesets to release 13 packages

Name	Type
@biomejs/biome	Patch
@biomejs/cli-win32-x64	Patch
@biomejs/cli-win32-arm64	Patch
@biomejs/cli-darwin-x64	Patch
@biomejs/cli-darwin-arm64	Patch
@biomejs/cli-linux-x64	Patch
@biomejs/cli-linux-arm64	Patch
@biomejs/cli-linux-x64-musl	Patch
@biomejs/cli-linux-arm64-musl	Patch
@biomejs/wasm-web	Patch
@biomejs/wasm-bundler	Patch
@biomejs/wasm-nodejs	Patch
@biomejs/backend-jsonrpc	Patch

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[coderabbitai]

Walkthrough

This change adds an explicit parameters slot to the arrow_function GritQL pattern by updating Tree‑sitter mappings in generated data and in the codegen mapping. It adds a grit spec and a TypeScript test file demonstrating an arrow function with parameters and body. A changeset documenting the patch release and docs/messaging updates were also added. No public API or exported declarations were modified.

Possibly related PRs

• fix(biome_grit_patterns): properly handle name and value metavariables for JsxAttribute GritQL queries #8202 — similar update to legacy Tree‑sitter/Grit pattern slot mappings and codegen adjustments.
• fix(grit): correct JSX element slot indices for GritQL patterns #8411 — related changes to Tree‑sitter/Grit pattern slot mappings in generated mappings and codegen for another node kind.

Suggested labels

L-JavaScript

Suggested reviewers

• ematipico

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately captures the main change: adding missing parameters slot to the arrow_function GritQL pattern mapping.
Description check	✅ Passed	The description clearly explains the fix, motivation, and includes test verification with concrete examples of the resolved issue.

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[dyc3]

Nothing looks particularly wrong to me, but I'll pass it of to @morgante or @arendjr to approve.