readme: introduce gpustack

GPUStack is an open-source GPU cluster manager for running large
language models, which uses llama.cpp as the backend.

Signed-off-by: thxCode <thxcode0824@gmail.com>

README.md

@@ -190,6 +190,7 @@ Unless otherwise noted these projects are open-source with permissive licensing:
 **Infrastructure:**
 
 - [Paddler](https://github.com/distantmagic/paddler) - Stateful load balancer custom-tailored for llama.cpp
+- [GPUStack](https://github.com/gpustack/gpustack) - Manage GPU clusters for running LLMs
 
 **Games:**
 - [Lucy's Labyrinth](https://github.com/MorganRO8/Lucys_Labyrinth) - A simple maze game where agents controlled by an AI model will try to trick you.