feat(terraform): import Longhorn StorageClasses and app PVCs to Terraform state

- Phase 1: longhorn, longhorn-kafka StorageClasses (cluster-wide defaults)
- Phase 2 pilot: grafana, loki, portainer, forgejo PVCs
- All imports protected by lifecycle.prevent_destroy
- Removes Helm annotations (meta.helm.sh/*) to prevent dual-ownership conflicts
- Remote state backend (MinIO S3) syncs automatically on plan/apply
- Import-only approach: zero data loss, existing volumes untouched
- See terraform/LONGHORN_PVC_IMPORT.md for execution record

Co-Authored-By: Claude Haiku 4.5 <[email protected]>

terraform/grafana.tf

@@ -0,0 +1,24 @@
+# Grafana — persistent storage for dashboards and datasources
+# Imported from live cluster state (import-only, no delete)
+
+resource "kubernetes_persistent_volume_claim" "grafana" {
+  metadata {
+    name      = "grafana"
+    namespace = "logging"
+  }
+  spec {
+    access_modes       = ["ReadWriteOnce"]
+    storage_class_name = "longhorn"
+    resources {
+      requests = {
+        storage = "5Gi"
+      }
+    }
+    volume_name = "pvc-95f2216e-985d-4496-8b39-48e8c2a7f410"
+  }
+
+
+  lifecycle {
+    prevent_destroy = true
+  }
+}