fix: address remaining CodeQL alerts (#332)

src/utils/execFileNoThrow.test.ts

@@ -0,0 +1,25 @@
+import { expect, test } from 'bun:test'
+import { execFileNoThrowWithCwd } from './execFileNoThrow.js'
+
+test('execFileNoThrowWithCwd rejects shell-like executable names', async () => {
+  const result = await execFileNoThrowWithCwd('openclaude && whoami', [])
+
+  expect(result.code).toBe(1)
+  expect(result.error).toContain('Unsafe executable')
+})
+
+test('execFileNoThrowWithCwd rejects cwd values with control characters', async () => {
+  const result = await execFileNoThrowWithCwd(process.execPath, ['--version'], {
+    cwd: 'C:\\repo\nmalicious',
+  })
+
+  expect(result.code).toBe(1)
+  expect(result.error).toContain('Unsafe working directory')
+})
+
+test('execFileNoThrowWithCwd rejects arguments with control characters', async () => {
+  const result = await execFileNoThrowWithCwd(process.execPath, ['--version\nmalicious'])
+
+  expect(result.code).toBe(1)
+  expect(result.error).toContain('Unsafe argument')
+})