add express, automated mongodb atlas setup, fix stack architech

apps/cli/src/utils/command-exists.ts

@@ -0,0 +1,16 @@
+import { execa } from "execa";
+
+export async function commandExists(command: string): Promise<boolean> {
+	try {
+		const isWindows = process.platform === "win32";
+		if (isWindows) {
+			const result = await execa("where", [command]);
+			return result.exitCode === 0;
+		}
+
+		const result = await execa("which", [command]);
+		return result.exitCode === 0;
+	} catch {
+		return false;
+	}
+}