Chore: Convert background service registry to dskit module (#64062)

* Chore: Add initial support for deployment modes

* revert CLI changes and start modules independently

* add modules to codeowners

* additional comments

* add Engine and Manager interface to fix test issues

* convert background service registry to dskit module

* remove extra context from serviceListener logger

Co-authored-by: Will Browne <wbrowne@users.noreply.github.com>

* Remove whitespace

* fix import

* undo ide changes

* only register All by default

* with registry

* add test

* add comments

* re-add debug log

* fix import

* reorganize arg

* undo kind changes

* add provide service test

* fix import

* rejig systemd calls

* update codeowners

---------

Co-authored-by: Todd Treece <todd.treece@grafana.com>
Co-authored-by: Todd Treece <360020+toddtreece@users.noreply.github.com>

pkg/modules/modules.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/setting"
+	"github.com/grafana/grafana/pkg/systemd"
 )
 
 type Engine interface {
@@ -98,6 +99,13 @@ func (m *service) Run(ctx context.Context) error {
 		return err
 	}
 
+	err = m.serviceManager.AwaitHealthy(ctx)
+	if err != nil {
+		return err
+	}
+
+	systemd.NotifyReady(m.log)
+
 	err = m.serviceManager.AwaitStopped(ctx)
 	if err != nil {
 		return err