refactor: migrate to model-agnostic Sonnet/Haiku architecture

- Migrate all 48 Opus agents to Sonnet
- Optimize 35 execution-focused agents for Haiku
- Update README with hybrid orchestration patterns
- Simplify model configuration to use agnostic aliases

Final distribution: 97 Sonnet / 47 Haiku agents

plugins/cicd-automation/agents/cloud-architect.md

@@ -1,7 +1,7 @@
 ---
 name: cloud-architect
 description: Expert cloud architect specializing in AWS/Azure/GCP multi-cloud infrastructure design, advanced IaC (Terraform/OpenTofu/CDK), FinOps cost optimization, and modern architectural patterns. Masters serverless, microservices, security, compliance, and disaster recovery. Use PROACTIVELY for cloud architecture, cost optimization, migration planning, or multi-cloud strategies.
-model: opus
+model: sonnet
 ---
 
 You are a cloud architect specializing in scalable, cost-effective, and secure multi-cloud infrastructure design.

plugins/cicd-automation/agents/deployment-engineer.md

@@ -1,7 +1,7 @@
 ---
 name: deployment-engineer
 description: Expert deployment engineer specializing in modern CI/CD pipelines, GitOps workflows, and advanced deployment automation. Masters GitHub Actions, ArgoCD/Flux, progressive delivery, container security, and platform engineering. Handles zero-downtime deployments, security scanning, and developer experience optimization. Use PROACTIVELY for CI/CD design, GitOps implementation, or deployment automation.
-model: sonnet
+model: haiku
 ---
 
 You are a deployment engineer specializing in modern CI/CD pipelines, GitOps workflows, and advanced deployment automation.

plugins/cicd-automation/agents/devops-troubleshooter.md

@@ -1,7 +1,7 @@
 ---
 name: devops-troubleshooter
 description: Expert DevOps troubleshooter specializing in rapid incident response, advanced debugging, and modern observability. Masters log analysis, distributed tracing, Kubernetes debugging, performance optimization, and root cause analysis. Handles production outages, system reliability, and preventive monitoring. Use PROACTIVELY for debugging, incident response, or system troubleshooting.
-model: sonnet
+model: haiku
 ---
 
 You are a DevOps troubleshooter specializing in rapid incident response, advanced debugging, and modern observability practices.

plugins/cicd-automation/agents/kubernetes-architect.md

@@ -1,7 +1,7 @@
 ---
 name: kubernetes-architect
 description: Expert Kubernetes architect specializing in cloud-native infrastructure, advanced GitOps workflows (ArgoCD/Flux), and enterprise container orchestration. Masters EKS/AKS/GKE, service mesh (Istio/Linkerd), progressive delivery, multi-tenancy, and platform engineering. Handles security, observability, cost optimization, and developer experience. Use PROACTIVELY for K8s architecture, GitOps implementation, or cloud-native platform design.
-model: opus
+model: sonnet
 ---
 
 You are a Kubernetes architect specializing in cloud-native infrastructure, modern GitOps workflows, and enterprise container orchestration at scale.