Add Portworx CSI driver for Pure Storage FlashArray

- Deploy Portworx Operator + CSI driver via ArgoCD
- Support both iSCSI block and NFS file storage from FlashArray
- Integrate with 1Password External Secrets for FlashArray credentials
- Include comprehensive deployment documentation and validation script
- Storage classes: pure-block (iSCSI) and pure-file (NFS)
- Talos Linux compatible with iSCSI/multipath configuration

cluster/platform/portworx-csi/storageclass-block.yaml

@@ -0,0 +1,51 @@
+# ------------------------------------------------------------------------------
+# StorageClass: pure-block
+# Provisioner: pxd.portworx.com (Portworx CSI)
+# Backend: Pure Storage FlashArray (iSCSI block volumes)
+#
+# Use case: High-performance block storage for databases, stateful applications
+# Features:
+#   - Block-level access via iSCSI
+#   - Dynamic provisioning from FlashArray
+#   - RWO (ReadWriteOnce) access mode
+#   - Delete reclaim policy (volume deleted when PVC is deleted)
+#
+# Parameters:
+#   - backend: "pure-block" (uses FlashArray block volumes)
+#   - repl: "1" (single replica, FlashArray handles redundancy)
+#   - io_profile: "db_remote" (optimized for database workloads)
+# ------------------------------------------------------------------------------
+apiVersion: storage.k8s.io/v1
+kind: StorageClass
+metadata:
+  name: pure-block
+  annotations:
+    storageclass.kubernetes.io/is-default-class: "false"
+provisioner: pxd.portworx.com
+parameters:
+  # Backend type
+  backend: "pure-block"
+  
+  # Replication factor (FlashArray handles HA)
+  repl: "1"
+  
+  # I/O profile optimized for databases
+  io_profile: "db_remote"
+  
+  # Filesystem type
+  fs: "ext4"
+  
+  # Priority (higher number = higher priority for placement)
+  priority_io: "high"
+
+# Reclaim policy
+reclaimPolicy: Delete
+
+# Volume binding mode
+volumeBindingMode: Immediate
+
+# Allow volume expansion
+allowVolumeExpansion: true
+
+# Mount options
+mountOptions: []