Fix #106530: Don't try to move unmovable node socket values

Missing checkings for unsupported cases.

Pull Request: https://projects.blender.org/blender/blender/pulls/106545

source/blender/blenkernel/intern/node.cc

@@ -2477,11 +2477,21 @@ void node_socket_move_default_value(Main &bmain,
       }
       break;
     }
+    case SOCK_CUSTOM:
+    case SOCK_SHADER:
+    case SOCK_GEOMETRY: {
+      /* Unmovable types. */
+      return;
+    }
     default: {
       break;
     }
   }
 
+  if (dst_values.is_empty() || src_socket_value == nullptr) {
+    return;
+  }
+
   for (ID **dst_value : dst_values) {
     *dst_value = *src_socket_value;
     id_us_plus(*dst_value);