feat: add script that is used to wait for the hub to become available

scripts/fraud_proof_poc/wait-for-hub.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+
+# Target URL
+URL="http://hub:36657/status"
+
+# Wait for the /status endpoint to be available and the latest_block_height to be present
+while true; do
+    # Use curl to fetch the status endpoint and jq to parse the JSON response
+    HEIGHT=$(curl -s $URL | jq -r '.result.sync_info.latest_block_height')
+
+    # Check if HEIGHT is a number and greater than 0 (modify this check as needed)
+    if [[ "$HEIGHT" =~ ^[0-9]+$ ]] && [ "$HEIGHT" -gt 0 ]; then
+        echo "hub is ready with latest_block_height: $HEIGHT"
+        break
+    else
+        echo "Waiting for hub to be ready..."
+    fi
+
+    sleep 5 # Wait for 5 seconds before trying again
+done
+
+# Proceed with the rest of your script or command to start the service
+exec "$@"