Address PR review feedback: shell-safe spawn, test cleanup

- Use spawn with shell:true instead of splitting gitCmd on whitespace,
  which broke quoted arguments and paths with spaces (Comment 1)
- Remove unused unlinkSync import (Comment 5)
- Add afterAll cleanup for temp test directory (Comment 6)

https://claude.ai/code/session_01XGR7aJPmEZuK4j8r9HSodB

Author: claude

src/__tests__/buildCredentialQuerier.test.ts

@@ -1,5 +1,5 @@
 import { buildCredentialQuerier } from "../server/buildCredentialQuerier"
-import { writeFileSync, unlinkSync, mkdtempSync } from "fs"
+import { writeFileSync, mkdtempSync, rmSync } from "fs"
 import { join } from "path"
 import { tmpdir } from "os"
 
@@ -12,6 +12,10 @@ beforeAll(() => {
   tmpDir = mkdtempSync(join(tmpdir(), "gcf-test-"))
 })
 
+afterAll(() => {
+  rmSync(tmpDir, { recursive: true, force: true })
+})
+
 function writeMockScript(name: string, code: string): string {
   const path = join(tmpDir, name)
   writeFileSync(path, code)

src/server/buildCredentialQuerier.ts

@@ -66,14 +66,12 @@ async function runCredentialAction(
   const GIT_CREDENTIAL_ARG = "credential"
   const inputSerialized = gitCredentialIoApi.serialize(input)
 
-  const [cmd, ...cmdArgs] = gitCmd.split(/\s+/) as [string, ...string[]]
-  const args = [...cmdArgs, GIT_CREDENTIAL_ARG, action]
+  const fullCmd = `${gitCmd} ${GIT_CREDENTIAL_ARG} ${action}`
 
-  debug(`Running: ${cmd} ${args.join(" ")} (with stdin piping)`)
+  debug(`Running: ${fullCmd} (with stdin piping)`)
 
   const { stdout, stderr } = await spawnWithStdin(
-    cmd,
-    args,
+    fullCmd,
     inputSerialized + "\n",
     env
   ).catch(err => {
@@ -97,13 +95,13 @@ async function runCredentialAction(
 
 function spawnWithStdin(
   cmd: string,
-  args: string[],
   stdinData: string,
   env: NodeJS.ProcessEnv
 ): Promise<{ stdout: string; stderr: string }> {
   return new Promise((resolve, reject) => {
-    const child = spawn(cmd, args, {
+    const child = spawn(cmd, {
       env,
+      shell: true,
       stdio: ["pipe", "pipe", "pipe"]
     })