[BUG][dataprotection@2025-07-01] `BackupInstances_CreateOrUpdate` is already LRO but can not gurantee the `protectionStatus`

### API Spec link

https://github.com/Azure/azure-rest-api-specs/blob/dcaa77fcd61105315164a986dd185219331a76a5/specification/dataprotection/resource-manager/Microsoft.DataProtection/DataProtection/stable/2025-07-01/dataprotection.json#L817

### API Spec version

2025-07-01

### Describe the bug

Thou it's already an LRO, when the LRO is returned with `Succeeded`, a following get on the backup isntance may still get
```
"protectionStatus": {
"status": "ConfiguringProtection"
},
"currentProtectionState": "ConfiguringProtection",
```

### Expected behavior

the `currentProtectionState` and `protectionStatus.status` can be updated at the same time as the LRO return successfully.

### Actual behavior

as description

### Reproduction Steps

create a backup isntance

### Environment

_No response_

Start with the dataprotection.json API specification at the linked operation around line 817, then follow the create-a-backup-instance reproduction described in the issue. A complete fix should ensure that a successful long-running operation is followed by a GET showing currentProtectionState and protectionStatus.status updated together, though the issue does not identify an implementation file or test.

Written by the indexing model from the issue text.