<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#49489
Custom host vitals were skipped when host name template enforcement
(#38806) shipped, since both features were in development at the same
time. This adds `$FLEET_HOST_VITAL_<id>` support to host name templates,
matching the existing secret-variable pattern (validation, per-host
resolution, resend on value change).
I also introduced a new `IsInvalidReferencedCustomHostVitalsError` call
after Copilot's comment below.
# Checklist for submitter
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## Summary by CodeRabbit
* **New Features**
* Added support for `$FLEET_HOST_VITAL_<id>` in Apple host name
templates.
* Device-name template reconciliation now expands referenced per-host
vital values and updates automatically when those values change.
* **Bug Fixes**
* Prevents deleting custom host vitals that are referenced by host name
templates.
* If a referenced vital has no value for a host, device-name delivery is
marked failed for that host (retryable).
* **Improved Error Handling**
* Refined validation behavior so unknown/malformed vital references
return user-facing invalid-argument errors, while infrastructure errors
propagate unchanged.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Nico
87c1a719c1