refactor: centralize isPlainObject, isRecord, isErrno, isLoopbackHost utilities (#12926)

src/infra/ports-inspect.ts

@@ -1,6 +1,7 @@
 import net from "node:net";
 import type { PortListener, PortUsage, PortUsageStatus } from "./ports-types.js";
 import { runCommandWithTimeout } from "../process/exec.js";
+import { isErrno } from "./errors.js";
 import { buildPortHints } from "./ports-format.js";
 import { resolveLsofCommand } from "./ports-lsof.js";
 
@@ -11,10 +12,6 @@ type CommandResult = {
   error?: string;
 };
 
-function isErrno(err: unknown): err is NodeJS.ErrnoException {
-  return Boolean(err && typeof err === "object" && "code" in err);
-}
-
 async function runCommandSafe(argv: string[], timeoutMs = 5_000): Promise<CommandResult> {
   try {
     const res = await runCommandWithTimeout(argv, { timeoutMs });