Upgrade leanSpec to ad9a322 (devnet4: separate attestation and proposal keys)

  This commit introduces the dual-key model where validators have distinct
  attestation and proposal XMSS keys. Test fixture generation is blocked
  until leansig-test-keys publishes keys in the new format.

Author: pablodeymo

Makefile

@@ -24,7 +24,7 @@ docker-build: ## 🐳 Build the Docker image
 		-t ghcr.io/lambdaclass/ethlambda:$(DOCKER_TAG) .
 	@echo
 
-LEAN_SPEC_COMMIT_HASH:=d39d10195414921e979e2fdd43723d89cee13c8b
+LEAN_SPEC_COMMIT_HASH:=ad9a3226f55e1ba143e0991010ff1f6c2de62941
 
 leanSpec:
 	git clone https://github.com/leanEthereum/leanSpec.git --single-branch