Add Flux GitOps bootstrap for minikube

Set up a complete GitOps pipeline using Flux CD to manage a minikube
cluster. Includes bootstrap script, Traefik ingress controller via
HelmRelease, and a hello-world nginx deployment.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

clusters/minikube/infrastructure.yaml

@@ -0,0 +1,15 @@
+---
+apiVersion: kustomize.toolkit.fluxcd.io/v1
+kind: Kustomization
+metadata:
+  name: infrastructure
+  namespace: flux-system
+spec:
+  interval: 10m0s
+  path: ./infrastructure
+  prune: true
+  sourceRef:
+    kind: GitRepository
+    name: flux-system
+  wait: true
+  timeout: 5m0s