fix(packages/atst): Modify README.md with the new directory

packages/atst/src/README.md

@@ -22,6 +22,10 @@ CLI implementations of atst read and write
 
 Internal and external constants
 
+## contracts
+
+The attestation station contract
+
 ## lib
 
 All library code for the sdk lives here
@@ -32,4 +36,4 @@ Test helpers
 
 ## types
 
-Zod and typscript types
\ No newline at end of file
+Zod and typscript types