Access Control: Move part of access control database (#40483)

* Add accesscontrol migrations

* Add ResourceStore interface and related structs

* Add team/user/builtin-role

* Add accesscontrol database with functions to handle managed roles and
permissions

* Add ResourceManager

* Add GetUserPermissions

* Update pkg/services/accesscontrol/accesscontrol.go

Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>

pkg/services/accesscontrol/database/uid.go

@@ -0,0 +1,26 @@
+package database
+
+import (
+	"fmt"
+
+	"github.com/grafana/grafana/pkg/services/accesscontrol"
+	"github.com/grafana/grafana/pkg/services/sqlstore"
+	"github.com/grafana/grafana/pkg/util"
+)
+
+func generateNewRoleUID(sess *sqlstore.DBSession, orgID int64) (string, error) {
+	for i := 0; i < 3; i++ {
+		uid := util.GenerateShortUID()
+
+		exists, err := sess.Where("org_id=? AND uid=?", orgID, uid).Get(&accesscontrol.Role{})
+		if err != nil {
+			return "", err
+		}
+
+		if !exists {
+			return uid, nil
+		}
+	}
+
+	return "", fmt.Errorf("failed to generate uid")
+}