feat(coderd): add has_external_agent flag to template_versions and workspace_builds (#19285)

This pull request introduces support for external workspace management, allowing users to register and manage workspaces that are provisioned and managed outside of the Coder.

* Added has_external_agent field to workspace builds and template versions

coderd/database/modelqueries.go

@@ -84,6 +84,7 @@ func (q *sqlQuerier) GetAuthorizedTemplates(ctx context.Context, arg GetTemplate
 		arg.HasAITask,
 		arg.AuthorID,
 		arg.AuthorUsername,
+		arg.HasExternalAgent,
 	)
 	if err != nil {
 		return nil, err
@@ -271,6 +272,7 @@ func (q *sqlQuerier) GetAuthorizedWorkspaces(ctx context.Context, arg GetWorkspa
 		arg.LastUsedAfter,
 		arg.UsingActive,
 		arg.HasAITask,
+		arg.HasExternalAgent,
 		arg.RequesterID,
 		arg.Offset,
 		arg.Limit,
@@ -321,6 +323,7 @@ func (q *sqlQuerier) GetAuthorizedWorkspaces(ctx context.Context, arg GetWorkspa
 			&i.LatestBuildTransition,
 			&i.LatestBuildStatus,
 			&i.LatestBuildHasAITask,
+			&i.LatestBuildHasExternalAgent,
 			&i.Count,
 		); err != nil {
 			return nil, err