fix: harden port listener detection

src/infra/ports-lsof.ts

@@ -0,0 +1,35 @@
+import fs from "node:fs";
+import fsPromises from "node:fs/promises";
+
+const LSOF_CANDIDATES =
+  process.platform === "darwin"
+    ? ["/usr/sbin/lsof", "/usr/bin/lsof"]
+    : ["/usr/bin/lsof", "/usr/sbin/lsof"];
+
+async function canExecute(path: string): Promise<boolean> {
+  try {
+    await fsPromises.access(path, fs.constants.X_OK);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+export async function resolveLsofCommand(): Promise<string> {
+  for (const candidate of LSOF_CANDIDATES) {
+    if (await canExecute(candidate)) return candidate;
+  }
+  return "lsof";
+}
+
+export function resolveLsofCommandSync(): string {
+  for (const candidate of LSOF_CANDIDATES) {
+    try {
+      fs.accessSync(candidate, fs.constants.X_OK);
+      return candidate;
+    } catch {
+      // keep trying
+    }
+  }
+  return "lsof";
+}