fix: improve host diagnostics, storage handling, and maintenance workflows

- add zero-downtime Proxmox TLS certificate refresh from the Security panel (#307)
- classify storage availability independently from missing capacity information (#309)
- update ZFS ARC sizing and safely reconcile conflicting module configurations
- preserve and restore migrated ZFS settings without overwriting later administrator changes
- stop memory optimization from forcing the kernel overcommit policy
- correlate multi-line OOM events and identify the affected LXC, cgroup limits, swap and killed process
- add selectable Bash prompt path styles and clearer shell activation guidance
- protect technical names during automatic translation and correct localized terminology
- update the Coral and VM/LXC Apps and Updates documentation, translations and screenshots

AppImage/components/virtual-machines.tsx

@@ -5296,10 +5296,9 @@ const handleDownloadLogs = async (vmid: number, vmName: string) => {
                                       </button>
                                     </div>
                                     <div className="text-xs text-muted-foreground mb-3 leading-relaxed">
-                                      {t("vmLxc.updates.dockerImagesReadOnly")}
-                                      {selectedVM.docker_inventory.checked_at
-                                        ? ` · ${t("vmLxc.updates.lastCheckedPrefix")} ${new Date(selectedVM.docker_inventory.checked_at).toLocaleString()}`
-                                        : ""}
+                                      {t("vmLxc.updates.lastCheckedPrefix")} {selectedVM.docker_inventory.checked_at
+                                        ? new Date(selectedVM.docker_inventory.checked_at).toLocaleString()
+                                        : "—"}
                                     </div>
                                     {dockerInventoryRefreshing ? (
                                       <div className="text-sm text-muted-foreground flex items-center gap-2">