Report PPS Type in KVP / Azure Heath Reports

In the `build_success_health_report()` and `build_failure_health_report()` methods, we build the formatted health report for ingestion by Azure. Instead of hardcoding the PPS value, assign it using the extended IMDS call.

Initial Request:
"Can you file issue to correctly report the pps_type? - this can be retrieved from the extended IMDS call (which we're already using)"

_Originally posted by @anhvoms in https://github.com/Azure/azure-init/pull/188#discussion_r2054782038_

This may require updating the Compute to something like this--
```rust
#[derive(Debug, Deserialize, PartialEq, Clone)]
pub struct Compute {
#[serde(rename = "osProfile")]
pub os_profile: OsProfile,

#[serde(rename = "publicKeys")]
pub public_keys: Vec,

#[serde(rename = "ppsType")]
pub pps_type: Option,
}
```

Locate build_success_health_report() and build_failure_health_report(), then trace the extended IMDS response into the Compute model. Check how the health report is formatted for Azure ingestion and confirm that pps_type comes from the response rather than a hardcoded value.

Written by the indexing model from the issue text.