[ci skip] fix: add mount_options to all NFS PVs (soft,timeo=30,retrans=3)

Critical fix: StorageClass mountOptions only apply during dynamic
provisioning. Our static PVs (created by Terraform) were missing
mount_options, so all NFS mounts defaulted to hard,timeo=600 —
the exact stale mount behavior we were trying to eliminate.

Adds mount_options directly to the nfs_volume module PV spec and
to the monitoring PVs (prometheus, loki, alertmanager).

Requires re-applying all stacks to propagate to existing PVs.

stacks/platform/modules/monitoring/grafana.tf

@@ -43,6 +43,12 @@ resource "kubernetes_persistent_volume" "alertmanager_pv" {
         }
       }
     }
+    mount_options = [
+      "soft",
+      "timeo=30",
+      "retrans=3",
+      "actimeo=5",
+    ]
     storage_class_name = "nfs-truenas"
   }
 }

stacks/platform/modules/monitoring/loki.tf

@@ -33,6 +33,12 @@ resource "kubernetes_persistent_volume" "loki" {
         }
       }
     }
+    mount_options = [
+      "soft",
+      "timeo=30",
+      "retrans=3",
+      "actimeo=5",
+    ]
     storage_class_name               = "nfs-truenas"
     persistent_volume_reclaim_policy = "Retain"
     volume_mode                      = "Filesystem"

stacks/platform/modules/monitoring/prometheus.tf

@@ -38,6 +38,12 @@ resource "kubernetes_persistent_volume" "prometheus_server_pvc" {
         }
       }
     }
+    mount_options = [
+      "soft",
+      "timeo=30",
+      "retrans=3",
+      "actimeo=5",
+    ]
     storage_class_name               = "nfs-truenas"
     persistent_volume_reclaim_policy = "Retain"
     volume_mode                      = "Filesystem"