Bump version to v3.1.1: Add README reference to the lock variant for concurrency 1 use case

Author: ori88c

README.md

@@ -11,7 +11,9 @@ The design addresses the two primary semaphore use cases in Node.js:
 
 Each use case necessitates distinct handling capabilities, which will be discussed separately with accompanying examples.
 
-If your use case involves weighted jobs — where instead of limiting the maximum concurrency, you need to enforce a maximum total weight for concurrently executing jobs — consider using the weighted variant of this package: [zero-backpressure-weighted-promise-semaphore](https://www.npmjs.com/package/zero-backpressure-weighted-promise-semaphore).
+If your use case involves weighted jobs - where instead of limiting the maximum concurrency, you need to enforce a maximum total weight for concurrently executing jobs - consider using the weighted variant of this package: [zero-backpressure-weighted-promise-semaphore](https://www.npmjs.com/package/zero-backpressure-weighted-promise-semaphore).
+
+If your use case requires a concurrency of 1, consider using the lock variant of this package: [zero-overhead-promise-lock](https://www.npmjs.com/package/zero-overhead-promise-lock). While semaphores can simulate locks by setting their concurrency to 1, a dedicated lock implementation offers greater efficiency with minimal overhead.
 
 ## Table of Contents
 

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "zero-backpressure-semaphore-typescript",
-  "version": "3.1.0",
+  "version": "3.1.1",
   "description": "A modern Promise-semaphore for Node.js projects, enabling users to limit the number of concurrently executing promises. Offering backpressure control for enhanced efficiency, utilizing a communicative API that signals availability, promoting a just-in-time approach. Additionally, it incorporates mechanisms for graceful termination and error handling, making it suitable for complex scenarios.",
   "repository": {
     "type": "git",