Add archive notice to README (#85)

Update readme with notice of archive/move to sei-chain.

Author: masih

README.md

@@ -1,3 +1,7 @@
+
+> [!IMPORTANT]
+> This repository has been archived and is moved to [`sei-chain`](https://github.com/sei-protocol/sei-chain) as a nested module.
+
 # Wasm Zone
 
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