macOS: Instance is suspended after killing the daemon and cannot be restarted or stopped

**Describe the bug**
I was using the 1.14 RC5 macOS GUI client and it crashed unexpectedly when I switched off the "Allow privileged mounts" setting. The daemon caused it to suspend a running instance, which didn't suspend as expected and the daemon failed to quit, with the image becoming corrupted. I had to kill processes manually to be able to use Multipass again. The affected instance is still in suspended mode and cannot be started or stopped (even with --force option).

**Logs**
[multipassd.log.zip](https://github.com/user-attachments/files/16130651/multipassd.log.zip)

**Additional info**
- OS: MacBook Air M1, macOS Sonoma 14.5
- `multipass version`:
```
multipass 1.14.0-rc5+mac.2461+gd7835f5fc.mac
multipassd 1.14.0-rc5+mac.2461+gd7835f5fc.mac
```
- `multipass info`: [multipass-info.txt](https://github.com/user-attachments/files/16130640/multipass-info.txt)
- `multipass get local.driver`: qemu

Start with multipassd.log.zip and multipass-info.txt, then trace the daemon and instance lifecycle around the macOS GUI's "Allow privileged mounts" setting and the CLI --force start/stop paths. Done means an instance is not left unrecoverably suspended after the daemon is killed, and can be started or stopped without image corruption.

Written by the indexing model from the issue text.