slog migration: service layer + subsystem libraries (#40661)

<!-- Add the related story/sub-task/bug number, like Resolves #123, or
remove if NA -->
**Related issue:** Resolves #40540 

# Checklist for submitter

- [ ] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
  - Changes present in previous PR

## 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

* **Refactor**
* Updated internal logging infrastructure to improve consistency and
maintainability across the application.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

tools/mdm/apple/apnspush/main.go

@@ -87,7 +87,7 @@ func main() {
 		})), nil
 	}))
 
-	nanoMDMLogger := service.NewNanoMDMLogger(logger.With("component", "apple-mdm-push"))
+	nanoMDMLogger := service.NewNanoMDMLogger(logger.With("component", "apple-mdm-push").SlogLogger())
 	pusher := nanomdm_pushsvc.New(mdmStorage, mdmStorage, pushProviderFactory, nanoMDMLogger)
 	res, err := pusher.Push(context.Background(), hostUUIDs)
 	if err != nil {