VM deployment randomly fails on XCP-ng 8.3 due to stale template_spool_ref

### problem

We are experiencing intermittent/random VM deployment failures in CloudStack 4.22.1 with XCP-ng 8.3.

During the investigation, we observed that the template copy/base volume associated with the deployment is no longer present in the primary storage. However, the corresponding database entry still exists in the template_spool_ref table.

When CloudStack subsequently attempts to deploy a VM from the affected template, it appears to retrieve the stale storage reference from the database and attempts to access a VDI that no longer exists.

The deployment then fails with an XCP-ng API error indicating that the VDI UUID is invalid.

### versions

Apache CloudStack: 4.22.1
Hypervisor: XCP-ng 8.3
Storage: Presetup [iSCSI]

### The steps to reproduce the bug

VM Launch is failing below is observed in logs:
```

2026-09-08 15:02:51,295 ERROR [o.a.c.e.o.VolumeOrchestrator] (Work-Job-Executor-51:[ctx-21e4a1d0, job-5595/job-5596, ctx-af6a6525]) (logid:0b1aca2f) Unable to create volume [{"name":"ROOT-449","uuid":"6871902e-df60-4d42-9b9a-7dd2851e0c1b"}] due to [com.cloud.utils.exception.CloudRuntimeException: Catch Exception com.xensource.xenapi.Types$UuidInvalid :VDI getByUuid for uuid: 85032e3f-3d1a-4336-af29-4b7039fc71a0 failed due to The uuid you supplied was invalid.].
2026-09-08 15:02:51,295 WARN [c.c.v.ClusteredVirtualMachineManagerImpl] (Work-Job-Executor-51:[ctx-21e4a1d0, job-5595/job-5596, ctx-af6a6525]) (logid:0b1aca2f) Unable to contact resource. com.cloud.exception.StorageUnavailableException: Resource [StoragePool:1] is unreachable: Unable to create volume [{"name":"ROOT-449","uuid":"6871902e-df60-4d42-9b9a-7dd2851e0c1b"}] due to [com.cloud.utils.exception.CloudRuntimeException: Catch Exception com.xensource.xenapi.Types$UuidInvalid :VDI getByUuid for uuid: 85032e3f-3d1a-4336-af29-4b7039fc71a0 failed due to The uuid you supplied was invalid.].
```

### What to do about it?

Should the corresponding template_spool_ref entry be removed or marked appropriately when the template copy is deleted?

Bắt đầu bằng cách theo dõi cách các mục template_spool_ref được tạo và xử lý khi một bản sao template hoặc volume cơ sở bị xóa, sử dụng lỗi triển khai XCP-ng đã được báo cáo làm tín hiệu tái hiện. Xác định hành vi dọn dẹp phù hợp và xác minh rằng việc triển khai từ một template bị ảnh hưởng không còn cố truy cập vào một VDI không tồn tại.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.