Added. a Splunk Buidl doc

Author: hagen-p

SPLUNK-BUILD.md

@@ -0,0 +1,48 @@
+# Building the Splunk version of the  OpenTelemetry Demo Webstore
+
+Welcome to the Splunk fork of the OpenTelemetry Demo repository!
+This fork streamlines the default OpenTelemetry Demo by removing components not used with Splunk and updating several services to better demonstrate Splunk Observability (O11y) features.
+
+
+## Getting Started
+
+This deployment assumes you are using Kubernetes — for example, with platforms such as minikube or k3s.
+The deployment manifests are located in the kubernetes/ folder, with the main file named opentelemetry-demo.yaml.
+
+This file has been adapted to deploy both:
+* The default OpenTelemetry Demo services, and
+* Splunk-specific components and configurations.
+
+### Adapted Services
+
+The following services have been updated or added in this Splunk version:
+
+* Frontend-proxy
+* Frontend
+* Image-provider
+* Accounting
+* Payment
+* Recommendation
+* Ad
+* Cart
+
+### Building the Services
+
+Each service directory under src/ contains a build script used to create its container image.
+For example, the Ad Service build script is located at: 
+[ad service build script](src/ad/build-ad.sh)
+
+Run the script directly. If executed without parameters, it displays the required usage information:
+
+```bash
+❌ Error: No version provided.
+Usage: ./build-ad.sh <version> [-cc] 
+```
+
+Ech script willl require a version tag such as 0.0.1 when running the script.
+Use the optional -cc flag to force a clean build and repull all base images and layers.
+
+After the build completes, the resulting image is pushed to: **ghcr.io/splunk/opentelemetry-demo/**
+
+If you have permission to push to this registry, make sure you are logged in beforehand.
+Otherwise, you can modify the build script to push the image to your own container registry and update the deployment file accordingly.