Verify VPP: core implementation (#30295)

# Checklist for submitter

If some of the following don't apply, delete the relevant line.

<!-- Note that API documentation changes are now addressed by the
product design team. -->

- [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.
- [x] Input data is properly validated, `SELECT *` is avoided, SQL
injection is prevented (using placeholders for values in statements)
- For database migrations:
- [x] Ensured the correct collation is explicitly set for character
columns (`COLLATE utf8mb4_unicode_ci`).
- [x] Added/updated automated tests
- [x] Manual QA for all new/changed functionality

server/service/testing_utils.go

@@ -406,13 +406,15 @@ func RunServerForTestsWithServiceWithDS(t *testing.T, ctx context.Context, ds fl
 		scepStorage := opts[0].SCEPStorage
 		commander := apple_mdm.NewMDMAppleCommander(mdmStorage, mdmPusher)
 		if mdmStorage != nil && scepStorage != nil {
+			checkInAndCommand := NewMDMAppleCheckinAndCommandService(ds, commander, logger)
+			checkInAndCommand.RegisterResultsHandler("InstalledApplicationList", NewInstalledApplicationListResultsHandler(ds, commander, logger, cfg.Server.VPPVerifyTimeout, cfg.Server.VPPVerifyRequestDelay))
 			err := RegisterAppleMDMProtocolServices(
 				rootMux,
 				cfg.MDM,
 				mdmStorage,
 				scepStorage,
 				logger,
-				NewMDMAppleCheckinAndCommandService(ds, commander, logger),
+				checkInAndCommand,
 				&MDMAppleDDMService{
 					ds:     ds,
 					logger: logger,