add archival notice

README.md

@@ -1,3 +1,10 @@
+# Archival Notice
+`beacon-network-ui` was developed for ELIXIR Beacon implementation studies [2018](https://elixir-europe.org/internal-projects/commissioned-services/beacon-network-service) and [2019-2021](https://elixir-europe.org/internal-projects/commissioned-services/beacon-2019-21). Development on the Beacon v1 specification has ceased, and a new Beacon v2 specification has been finalised, and is being adopted by beacon providers.
+
+Users are encouraged to move to the next iteration of [Beacon Network UI v2](https://github.com/elixir-europe/beacon-network-ui). Beacon v2 development can be followed at [GA4GH Beacon v2 Project](https://beacon-project.io/).
+
+We thank all parties that have been involved with us in the development of the Beacon v1 products past these years.
+
 ## Beacon Network UI
 
 [![End-to-end tests](https://github.com/CSCfi/beacon-network-ui/actions/workflows/E2Etests.yml/badge.svg)](https://github.com/CSCfi/beacon-network-ui/actions/workflows/E2Etests.yml)