[BUG] azurebackup vault create ignores --storage-type for Recovery Services vaults #3981

Describe the bug

azurebackup vault create --vault-type rsv accepts --storage-type but does not apply it. RsvBackupOperations.CreateVaultAsync receives storageType and never uses it. For --vault-type dpp the value is applied, and azurebackup vault update --redundancy sets it for RSV vaults through the backup storage config.

Expected behavior

The Recovery Services vault is created with the requested storage redundancy.

Actual behavior

Only the vault GET and PUT are sent; the backup storage config (backupstorageconfig/vaultstorageconfig) is never updated, so the vault keeps the default geo-redundant storage. The redundancy can only be changed before a backup is configured in the vault.

Reproduction Steps

Call azurebackup vault create with --vault-type rsv --storage-type LocallyRedundant and record the ARM requests: there is no request to backupstorageconfig/vaultstorageconfig.

Environment

main at bc89c9e.