feat: Add IntCode service in authentication

Implemented a new IntCode service within the authentication services. The service is responsible for generating a 6-digit random integer code using the randomatic module. This service will be used for OTP functionalities.

src/services/authentication/intcode.service.ts

@@ -0,0 +1,10 @@
+import randomatic from "randomatic";
+
+
+const IntCodeService = {
+	generate: () => {
+		return randomatic('0', 6)
+	}
+}
+
+export default IntCodeService;