Add comprehensive OpenShift deployment guide for vLLM

- Add new 05-openshift.adoc page with complete OpenShift deployment guide
- Include OpenShift-specific features: Routes, BuildConfigs, SCC, Network Policies
- Cover CI/CD with OpenShift Pipelines (Tekton)
- Add monitoring and observability with OpenShift's built-in stack
- Include security and compliance configurations
- Use standard Kubernetes Deployments instead of DeploymentConfig
- Remove Service Mesh section for simplified focus
- Update navigation and index pages to include OpenShift section
- Provide comprehensive troubleshooting guide

Author: blues-man

documentation/modules/ROOT/nav.adoc

@@ -25,4 +25,16 @@
 ** xref:04-kubernetes.adoc#autoscaling[Horizontal Pod Autoscaling]
 ** xref:04-kubernetes.adoc#ingress[Ingress Configuration]
 ** xref:04-kubernetes.adoc#monitoring[Monitoring & Observability]
-** xref:04-kubernetes.adoc#advanced-patterns[Advanced Deployment Patterns]
+** xref:04-kubernetes.adoc#advanced-patterns[Advanced Deployment Patterns]
+
+* xref:05-openshift.adoc[5. vLLM on OpenShift]
+** xref:05-openshift.adoc#openshift-setup[OpenShift Setup]
+** xref:05-openshift.adoc#basic-deployment[Basic Deployment]
+** xref:05-openshift.adoc#buildconfig[Build Configuration]
+** xref:05-openshift.adoc#persistent-storage[Persistent Storage]
+** xref:05-openshift.adoc#configmap-secrets[Configuration Management]
+** xref:05-openshift.adoc#autoscaling[Horizontal Pod Autoscaling]
+** xref:05-openshift.adoc#monitoring[Monitoring & Observability]
+** xref:05-openshift.adoc#security[Security & Compliance]
+** xref:05-openshift.adoc#cicd[CI/CD with OpenShift Pipelines]
+** xref:05-openshift.adoc#troubleshooting[Troubleshooting]