fix: handle local node execution without SSH in blockchain health check

- Detect when node is localhost or current hostname
- Execute commands directly on local node instead of using SSH
- Fixes SSH permission denied errors when checking services on local node
- gitea-runner runs the workflow, so it should check aitbc services directly

scripts/multi-node/blockchain-health-check.sh

@@ -57,7 +57,13 @@ log_warning() {
 ssh_exec() {
     local node="$1"
     local command="$2"
+    
+    # If node is localhost, execute directly without SSH
+    if [ "$node" = "localhost" ] || [ "$node" = "$(hostname)" ]; then
+        bash -c "$command" 2>&1 || return 1
+    else
         ssh -o ConnectTimeout=10 -o StrictHostKeyChecking=no "$node" "$command" 2>&1 || return 1
+    fi
 }
 
 # Check RPC endpoint health