fix: sanitize VM name + use qm disk import (newer Proxmox syntax)

- VM name now sanitized: spaces→hyphens, lowercase, strip invalid chars
- qm importdisk → qm disk import (newer Proxmox VE command)

backend/provisioner.py

@@ -270,9 +270,14 @@ def _process_job(job_id: str, req: JobSubmissionRequest):
         _update_job(job_id, status=JobStatus.IMPORTING_STORAGE, progress=70,
                      message="Creating VM...")
 
+        # Sanitize VM name: Proxmox requires DNS-safe names (a-z, 0-9, hyphens)
+        safe_name = re.sub(r'[^a-zA-Z0-9-]', '-', req.vm_name).strip('-').lower()
+        if not safe_name:
+            safe_name = f"vm-{vmid}"
+
         bios = "ovmf" if req.boot_type.value == "uefi" else "seabios"
         _run(["qm", "create", str(vmid),
-              "--name", req.vm_name,
+              "--name", safe_name,
               "--bios", bios,
               "--cores", str(req.cpu_cores),
               "--memory", str(req.ram_mb),
@@ -282,7 +287,7 @@ def _process_job(job_id: str, req: JobSubmissionRequest):
         # ── Import and attach each disk ────────────────────────────
         for idx, disk_path in enumerate(disk_paths):
             logger.info("Importing disk %d: %s", idx, disk_path)
-            result = _run(["qm", "importdisk", str(vmid), str(disk_path),
+            result = _run(["qm", "disk", "import", str(vmid), str(disk_path),
                            req.target_storage])
             output = result.stdout + result.stderr