NavTree: Make it possible to configure where in nav tree plugins live (#55484)

* NewIA: Plugin nav config

* progress

* Progress

* Things are working

* Add monitoring node

* Add alerts and incidents

* added experiment with standalone page

* Refactoring by adding a type for navtree root

* First test working

* More tests

* more tests

* Progress on richer config and sorting

* Sort weight working

* Path config

* Improving logic for not including admin or cfg nodes, making it the last step so that enterprise can add admin nodes without having to worry about the section not existing

* fixed index routes

* removed file

* Fixes

* Fixing tests

* Fixing more tests and adding support for weight config

* Updates

* Remove unused fake

* More fixes

* Minor tweak

* Minor fix

* Can now control position using sortweight even when existing items have no sortweight

* Added tests for frontend standalone page logic

* more tests

* Remove unused fake and fixed lint issue

* Moving reading settings to navtree impl package

* remove nav_id setting prefix

* Remove old test file

* Fix trailing newline

* Fixed bug with adding nil node

* fixing lint issue

* remove some code we have to rethink

* move read settings to PrivideService and switch to util.SplitString

pkg/api/dashboard_test.go

@@ -20,6 +20,7 @@ import (
 	"github.com/grafana/grafana/pkg/framework/coremodel/registry"
 	"github.com/grafana/grafana/pkg/infra/usagestats"
 	"github.com/grafana/grafana/pkg/models"
+	"github.com/grafana/grafana/pkg/plugins"
 	accesscontrolmock "github.com/grafana/grafana/pkg/services/accesscontrol/mock"
 	"github.com/grafana/grafana/pkg/services/alerting"
 	"github.com/grafana/grafana/pkg/services/annotations/annotationstest"
@@ -58,7 +59,7 @@ func TestGetHomeDashboard(t *testing.T) {
 
 	hs := &HTTPServer{
 		Cfg:                     cfg,
-		pluginStore:             &fakePluginStore{},
+		pluginStore:             &plugins.FakePluginStore{},
 		SQLStore:                mockstore.NewSQLStoreMock(),
 		preferenceService:       prefService,
 		dashboardVersionService: dashboardVersionService,
@@ -141,7 +142,7 @@ func TestDashboardAPIEndpoint(t *testing.T) {
 
 		hs := &HTTPServer{
 			Cfg:                     setting.NewCfg(),
-			pluginStore:             &fakePluginStore{},
+			pluginStore:             &plugins.FakePluginStore{},
 			SQLStore:                mockSQLStore,
 			AccessControl:           accesscontrolmock.New(),
 			Features:                featuremgmt.WithFeatures(),
@@ -1027,7 +1028,7 @@ func postDashboardScenario(t *testing.T, desc string, url string, routePattern s
 			QuotaService: &quotaimpl.Service{
 				Cfg: cfg,
 			},
-			pluginStore:           &fakePluginStore{},
+			pluginStore:           &plugins.FakePluginStore{},
 			LibraryPanelService:   &mockLibraryPanelService{},
 			LibraryElementService: &mockLibraryElementService{},
 			DashboardService:      dashboardService,