fix(aula-08): prevenir volume stalling com CSI tolerations e PDB

- Adicionar hcloud-csi-values.yaml com tolerations para node failures
- Configurar 2 replicas do CSI controller para HA
- Criar statefulset-pdb.yaml para proteger StatefulSets durante drain
- Documentar troubleshooting de volumes stuck no README

aula-08/statefulset-pdb.yaml

@@ -0,0 +1,12 @@
+# PodDisruptionBudget para proteger StatefulSets durante node drain
+# Evita que volumes fiquem stuck durante operacoes de manutencao
+apiVersion: policy/v1
+kind: PodDisruptionBudget
+metadata:
+  name: statefulset-pdb
+  namespace: default
+spec:
+  minAvailable: 0
+  selector:
+    matchLabels:
+      app.kubernetes.io/component: primary