example/dao: update makefile to compile zk proofs too

example/dao/Makefile

@@ -1,3 +1,13 @@
-# 
-dao:
-	RUST_LOG=debug cargo run --release
+PROOF_SRC = $(shell find proof -type f -name '*.zk')
+PROOF_BIN = $(PROOF_SRC:=.bin)
+
+ZKAS = ../../zkas
+
+dao: $(PROOF_BIN)
+	RUST_LOG=debug cargo run --release
+
+proof/%.zk.bin: proof/%.zk
+	$(ZKAS) $<
+
+clean:
+	rm -f $(PROOF_BIN)