problem: Bitcoin head check may lag because it checks it only once in 15 seconds

solution: use ZeroMQ connection to listen for new blocks

build.gradle

@@ -56,6 +56,7 @@ dependencies {
 
     implementation libs.bundles.grpc
     implementation libs.bundles.netty
+    implementation libs.zeromq
     implementation(libs.bundles.spring.framework) {
         exclude module: 'spring-boot-starter-logging'
     }