readme: clarify details about hardware requirements for AI plugins

Author: frenchwr

README.md

@@ -80,7 +80,7 @@ Now that your git metadata has been updated you are ready to create a bugfix bra
 
 ## OpenVINO™ AI Plugins
 
-This snap contains support for AI plugins running on Intel (CPU, GPU, and NPU) and arm64-based hardware using Intel's OpenVINO AI inference library. In order to use these plugins, please follow these steps:
+This snap contains support for AI plugins running on Intel hardware (CPU, GPU, and NPU) using Intel's OpenVINO AI inference library. In order to use these plugins, please follow these steps:
 
 
 1. **Install the plugins and their dependencies**:
@@ -93,7 +93,7 @@ This snap contains support for AI plugins running on Intel (CPU, GPU, and NPU) a
 
 2. **(Optional) Enable Intel NPU and GPU acceleration**:
 
-    If you are running on a machine equipped with an Intel neural processing unit (NPU) or graphics processing unit (GPU), ensure you have permissions to use these devices by adding yourself to the `render` Unix group:
+    If you are running on a machine (e.g. a laptop or desktop containing an Intel Core Ultra processor) equipped with an Intel neural processing unit (NPU) or graphics processing unit (GPU), ensure you have permissions to use these devices by adding yourself to the `render` Unix group:
 
     ```shell
     sudo usermod -a -G render $USER
@@ -112,6 +112,9 @@ This snap contains support for AI plugins running on Intel (CPU, GPU, and NPU) a
 
 3. **(Optional) Install stable diffusion models**:
 
+> [!IMPORTANT]
+> Running the stable diffusion plugin requires either an Intel GPU (integrated or discrete) or Intel NPU.
+
     Models for the super resolution and semantic segmentation plugins are relatively small and therefore built into the snap, while the stable diffusion models are each on the order of GBs and therefore downloaded to a user's home directory at `~/.local/share/openvino-ai-plugins-gimp` via one of two methods: a `model-setup` command-line tool or from within the GIMP application. To run the interactive command-line tool:
 
     ```shell