Value of Global setting "convert.vmware.instance.to.kvm.extra.params.allowed.list" is not appened to the Virt-v2v tool

### problem

Value of Global settng "convert.vmware.instance.to.kvm.extra.params.allowed.list" is not appened to the Virt-v2v tool

### versions

ACS 4.22

### The steps to reproduce the bug

1. Enable the global setting "convert.vmware.instance.to.kvm.extra.params.allowed"

2. Set the convert.vmware.instance.to.kvm.extra.params.allowed to a value say -x

3. Import a vmware from kvm

4. In the import from vmware form, do not select the option "Pass extra parameters to the virt-v2v command on the conversion host"

5. Check the agent logs on the kvm host

The global setting value "extra.params" are not passed to the virt-v2v tool

```
2026-04-13 12:24:59,796 DEBUG [resource.wrapper.LibvirtConvertInstanceCommandWrapper] (AgentRequest-Handler-5:[]) (logid:565d9bad) Executing command [virt-v2v --root first -i ova /mnt/6f0e9b83-ab0d-3cc5-8ac6-189c672fe035/d1fa1750-df2d-44ba-90dc-1a39696137b5/i-2-16-VM/ -o local -os /mnt/6f0e9b83-ab0d-3cc5-8ac6-189c672fe035 -of qcow2 -on 5ed4eabd-058a-400e-a3c8-fa8c215bfb26 -v ].

```

6. The extra param value (-x) is only passed when it's mentioned in the "import from vmware form"

```

2026-04-13 12:31:32,208 DEBUG [resource.wrapper.LibvirtConvertInstanceCommandWrapper] (AgentRequest-Handler-4:[]) (logid:79bdffdc) Executing command [virt-v2v --root first -i ova /mnt/6f0e9b83-ab0d-3cc5-8ac6-189c672fe035/229a4c65-7ebd-42d4-90a2-e51fd2064973/i-2-16-VM/ -o local -os /mnt/6f0e9b83-ab0d-3cc5-8ac6-189c672fe035 -of qcow2 -on 1c906a30-86b1-442a-be0b-39f0cc65abcc -v x

2026-04-13 12:34:02,504 DEBUG [resource.wrapper.LibvirtConvertInstanceCommandWrapper] (AgentRequest-Handler-1:[]) (logid:3ae94f9c) Executing command [virt-v2v --root first -i ova /mnt/6f0e9b83-ab0d-3cc5-8ac6-189c672fe035/b4bc39ad-3065-42c2-b9a7-eec1f6c87454/i-2-16-VM/ -o local -os /mnt/6f0e9b83-ab0d-3cc5-8ac6-189c672fe035 -of qcow2 -on 4addaa01-58bc-43a4-a9d9-b030be5dde46 -v -x ].

```

### What to do about it?

Expected behaviour

The extra parameter value mentioned in the global setting should get populated in the import instance form and admin should be able to select the parameters which could be passed on the the virt-v2v tool

Start by reproducing the VMware import workflow and reviewing the agent log showing the virt-v2v command without the global extra parameter. Trace how convert.vmware.instance.to.kvm.extra.params.allowed.list is loaded and how the import form handles extra parameters. Done means the setting populates the form and selected values reach virt-v2v when the form field is otherwise left unselected.

Written by the indexing model from the issue text.