feat: add documentation comments for Model and clientArg structures in resource.go

stackit/internal/services/postgresflexalpha/user/resource.go

@@ -33,6 +33,7 @@ var (
 	_ resource.ResourceWithModifyPlan  = &userResource{}
 )
 
+// Model represents the Terraform resource state for a PostgreSQL Flex user.
 type Model struct {
 	postgresflexalpha.UserModel
 	TerraformID types.String `tfsdk:"id"`
@@ -487,6 +488,7 @@ func (r *userResource) getUserResource(ctx context.Context, model *Model) (bool,
 	return true, nil
 }
 
+// clientArg holds the arguments for API calls.
 type clientArg struct {
 	projectId  string
 	instanceId string
@@ -516,6 +518,7 @@ func (r *userResource) setTFLogFields(ctx context.Context, model *Model) context
 	return ctx
 }
 
+// expandRoles converts a Terraform list of roles to a string slice.
 func (r *userResource) expandRoles(ctx context.Context, rolesSet types.List, diags *diag.Diagnostics) []string {
 	if rolesSet.IsNull() || rolesSet.IsUnknown() {
 		return nil