fix(vm_provision_mixin): cloud-init drive (ide2) needs images storage, not snippets

Proxmox's cloud-init drive is a disk image and requires a storage with
content='images' — the same requirement as the root disk — not the
snippets storage. These are commonly different storages (e.g. 'local'
with content=snippets-only, 'local-zfs' with content=images), and real
Proxmox now creates the VM fine but fails at *start* time with "storage
'X' does not support content-type 'images'" once it tries to generate
the cloud-init ISO.

Found live: a real deployment created the VM successfully, and only
failed when the user started it manually on the Proxmox side.

napalm_proxmox/vm_provision_mixin.py

@@ -375,7 +375,13 @@ class ProxmoxVMProvisionMixin:
             _logger.info(f"Setting Cloud-Init config for VM {vmid}")
 
             cloud_init_args = {
-                "ide2": f"{snippet_storage}:cloudinit",
+                # The cloud-init drive is a disk image — it needs a storage
+                # with content='images' (same requirement as the root disk),
+                # NOT the snippet storage (content='snippets'). These are
+                # often different storages; Proxmox fails at VM start with
+                # "storage 'X' does not support content-type 'images'" if
+                # this points at a snippets-only storage.
+                "ide2": f"{image_storage}:cloudinit",
                 "citype": "nocloud",
                 "cicustom": f"user={snippet_storage}:snippets/{filename}",
             }
@@ -546,9 +552,7 @@ class ProxmoxVMProvisionMixin:
             while True:
                 elapsed = time.time() - start_time
                 if wait_for_ip and elapsed > timeout:
-                    raise RuntimeError(
-                        f"VM {vmid} failed to acquire IP within {timeout}s"
-                    )
+                    raise RuntimeError(f"VM {vmid} failed to acquire IP within {timeout}s")
 
                 try:
                     # Query guest-agent network interfaces