fix(cli): resolve package updates on Windows

packages/cli/src/update.ts

@@ -63,14 +63,16 @@ const execFileAsync = promisify(execFile);
 
 /** Resolve every installed WRNexus dependency independently and in parallel. */
 export async function latestPackageVersions(names: string[]): Promise<Map<string, string>> {
-  const npm = process.platform === "win32" ? "npm.cmd" : "npm";
   const unique = [...new Set(names.filter((name) => name.startsWith("@wrnexus/")))];
   const entries = await Promise.all(
     unique.map(async (name) => {
       try {
-        const { stdout } = await execFileAsync(npm, ["view", name, "version", "--json"], {
-          encoding: "utf8",
-        });
+        const command = process.platform === "win32" ? (process.env.ComSpec ?? "cmd.exe") : "npm";
+        const args =
+          process.platform === "win32"
+            ? ["/d", "/s", "/c", "npm", "view", name, "version", "--json"]
+            : ["view", name, "version", "--json"];
+        const { stdout } = await execFileAsync(command, args, { encoding: "utf8" });
         const parsed = JSON.parse(stdout.trim()) as string | string[];
         const version = Array.isArray(parsed) ? parsed.at(-1) : parsed;
         return typeof version === "string" && /^\d+\.\d+\.\d+/.test(version)
@@ -1274,6 +1276,13 @@ export async function runUpdate(dir: string, args: string[]): Promise<void> {
     ? new Map<string, string>()
     : await latestPackageVersions(dependencyNames);
 
+  if (!versionArg && dependencyNames.length > 0 && packageVersions.size === 0) {
+    throw new Error(
+      `Unable to resolve any of ${new Set(dependencyNames).size} installed WRNexus package ` +
+        `version(s) from npm. Check the @wrnexus registry and authentication before retrying.`,
+    );
+  }
+
   console.log(`\n  ⚡ wrnexus update → migrations ${target}${dryRun ? "  (dry run)" : ""}`);
   if (!versionArg) {
     console.log(