fix: handle Windows EOF error in large-input hook test

Windows pipes raise EOF instead of EPIPE when the child process
exits before stdin finishes flushing. Added EOF to the ignored
error codes in runHookWithInput.

tests/integration/hooks.test.js

@@ -58,9 +58,10 @@ function runHookWithInput(scriptPath, input = {}, env = {}, timeoutMs = 10000) {
     proc.stdout.on('data', data => stdout += data);
     proc.stderr.on('data', data => stderr += data);
 
-    // Ignore EPIPE errors (process may exit before we finish writing)
+    // Ignore EPIPE/EOF errors (process may exit before we finish writing)
+    // Windows uses EOF instead of EPIPE for closed pipe writes
     proc.stdin.on('error', (err) => {
-      if (err.code !== 'EPIPE') {
+      if (err.code !== 'EPIPE' && err.code !== 'EOF') {
         reject(err);
       }
     });