Retire the OVA/OVF importers to unused/

Proxmox imports OVA/OVF natively now through a storage with the "import"
content type, or qm importovf. The built-in path also handles per-storage disk
format conversion, which neither script did.

Recorded the known bugs in each header rather than fixing them, since nothing
will run these again: import-ova-pve.py imports every VMDK but only attaches
disk-0, leaving multi-disk appliances partly orphaned, and assumes a
vm-<vmid>-disk-N name that not every storage type uses;
import-ova-to-proxmox.sh passes --format qcow2 unconditionally, which fails on
ZFS and LVM-thin.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

unused/import-ova-pve.py

@@ -1,4 +1,17 @@
 #!/usr/bin/env python3
+#
+# RETIRED. Kept for reference only.
+#
+# Proxmox imports OVA/OVF natively now, via a storage with the "import" content
+# type: upload the .ova there and use Create VM > Import, or `qm importovf`.
+# The built-in path handles disk format conversion per storage type, which this
+# script did not.
+#
+# Two known bugs, left unfixed since the script is retired:
+#   * every VMDK is imported in the loop, but only vm-<vmid>-disk-0 is ever
+#     attached, so multi-disk appliances leave the rest orphaned
+#   * the disk name is assumed to be vm-<vmid>-disk-N, which does not hold on
+#     every storage type
 
 import os
 import sys

unused/import-ova-to-proxmox.sh

@@ -1,4 +1,16 @@
 #!/bin/bash
+#
+# RETIRED. Kept for reference only.
+#
+# Proxmox imports OVA/OVF natively now, via a storage with the "import" content
+# type: upload the .ova there and use Create VM > Import, or `qm importovf`.
+# The built-in path handles disk format conversion per storage type, which this
+# script did not.
+#
+# Known bug, left unfixed since the script is retired: importdisk is called with
+# --format qcow2 unconditionally, which fails on ZFS and LVM-thin storages that
+# do not take a format argument.
+
 set -euo pipefail
 
 # === OVF/OVA Importer for Proxmox ===