[WIP] Plugins: Refactoring backend initialization flow (#42247)

* refactoring store interface and init flow

* fix import

* fix linter

* refactor resource calling

* load with class

* re-order args

* fix tests

* fix linter

* remove old creator

* add custom config struct

* fix some tests

* cleanup

* fix linter

* add connect failure error

* remove unused err

* convert test over

pkg/server/wireexts_oss.go

@@ -7,6 +7,7 @@ import (
 	"github.com/google/wire"
 	"github.com/grafana/grafana/pkg/models"
 	"github.com/grafana/grafana/pkg/plugins"
+	"github.com/grafana/grafana/pkg/plugins/backendplugin/provider"
 	"github.com/grafana/grafana/pkg/plugins/manager/signature"
 	"github.com/grafana/grafana/pkg/registry"
 	"github.com/grafana/grafana/pkg/server/backgroundsvcs"
@@ -61,6 +62,8 @@ var wireExtsBasicSet = wire.NewSet(
 	wire.Bind(new(searchusers.Service), new(*searchusers.OSSService)),
 	signature.ProvideService,
 	wire.Bind(new(plugins.PluginLoaderAuthorizer), new(*signature.UnsignedPluginAuthorizer)),
+	provider.ProvideService,
+	wire.Bind(new(plugins.BackendFactoryProvider), new(*provider.Service)),
 	acdb.ProvideService,
 	wire.Bind(new(accesscontrol.ResourcePermissionsStore), new(*acdb.AccessControlStore)),
 	wire.Bind(new(accesscontrol.PermissionsProvider), new(*acdb.AccessControlStore)),