Enhance Discord role management by adding hoist functionality

This commit introduces a new `hoist` attribute for Discord roles, allowing team roles and the registered role to be displayed in separate groups within the Discord member list. The `RoleWorker` has been updated to ensure team roles are positioned above the registered role, improving visibility and organization. Database schema changes have been made to support the new `hoist` field, and corresponding updates have been implemented in the service layer and tests to validate the new behavior.

backend/internal/application/discord_roles.go

@@ -33,6 +33,7 @@ type DiscordManagedRole struct {
 	Kind          string
 	DiscordRoleID string
 	RoleName      string
+	Hoist         bool
 }
 
 type DiscordRoleSyncJob struct {