feat: refactor data source models and update mapping functions for improved consistency

stackit/internal/services/sqlserverflexbeta/instance/datasource.go

@@ -6,6 +6,7 @@ import (
 	"net/http"
 
 	"github.com/hashicorp/terraform-plugin-framework/datasource"
+	"github.com/hashicorp/terraform-plugin-framework/types"
 	"github.com/hashicorp/terraform-plugin-log/tflog"
 	"github.com/stackitcloud/stackit-sdk-go/core/config"
 	"tf-provider.git.onstackit.cloud/stackit-dev-tools/terraform-provider-stackitprivatepreview/stackit/internal/conversion"
@@ -25,12 +26,22 @@ func NewInstanceDataSource() datasource.DataSource {
 	return &instanceDataSource{}
 }
 
+// dataSourceModel maps the data source schema data.
+type dataSourceModel struct {
+	sqlserverflexbetaGen.InstanceModel
+	TerraformID types.String `tfsdk:"id"`
+}
+
 type instanceDataSource struct {
 	client       *sqlserverflexbetaPkg.APIClient
 	providerData core.ProviderData
 }
 
-func (d *instanceDataSource) Metadata(_ context.Context, req datasource.MetadataRequest, resp *datasource.MetadataResponse) {
+func (d *instanceDataSource) Metadata(
+	_ context.Context,
+	req datasource.MetadataRequest,
+	resp *datasource.MetadataResponse,
+) {
 	resp.TypeName = req.ProviderTypeName + "_sqlserverflexbeta_instance"
 }
 
@@ -81,7 +92,7 @@ func (d *instanceDataSource) Configure(
 }
 
 func (d *instanceDataSource) Read(ctx context.Context, req datasource.ReadRequest, resp *datasource.ReadResponse) {
-	var data sqlserverflexbetaGen.InstanceModel
+	var data dataSourceModel
 
 	// Read Terraform configuration data into the model
 	resp.Diagnostics.Append(req.Config.Get(ctx, &data)...)