Add deprecation note

README.md

@@ -1,6 +1,9 @@
 # Terraform Provider Instana
 
-![CI/CD Build](https://github.com/gessnerfl/terraform-provider-instana/workflows/CICD/badge.svg)
+> [!CAUTION]
+> Deprecated. This project was handed over to the IBM Instana engineering teams and will be maintained by them. Please use the official IBM Instana terraform provider [https://github.com/instana/terraform-provider-instana](https://github.com/instana/terraform-provider-instana).
+
+[![Build, Test and Verify](https://github.com/gessnerfl/terraform-provider-instana/actions/workflows/build.yml/badge.svg)](https://github.com/gessnerfl/terraform-provider-instana/actions/workflows/build.yml)
 [![Quality Gate Status](https://sonarcloud.io/api/project_badges/measure?project=de.gessnerfl.terraform-provider-instana&metric=alert_status)](https://sonarcloud.io/dashboard?id=de.gessnerfl.terraform-provider-instana)
 
 Terraform provider implementation for the Instana REST API.

docs/index.md

@@ -1,4 +1,6 @@
-# instana Provider
+# Instana Provider
+
+**Deprecated:** This terraform provider is deprecated. Please use the official IBM Instana terraform provider [https://registry.terraform.io/providers/instana/instana/latest](https://registry.terraform.io/providers/instana/instana/latest).
 
 Terraform provider implementation of the Instana Web REST API. The provider can be used to configure different
 assents in Instana. The provider is aligned with the REST API and links to the endpoint is provided for each