Update README.md

Author: tilo-14

README.md

@@ -26,6 +26,10 @@ full compressed account lifecycle (create, increment, decrement, reset, close):
 
 - **[account-comparison](./account-comparison/)** - Compare compressed vs regular Solana accounts.
 
+### zk-id Program
+
+- **[zk-id](./zk-id)** - A minimal zk id Solana program that uses zero-knowledge proofs for identity verification with compressed accounts.
+
 
 ## Light Protocol dependencies