X_LIVE_SERVER_RENDER
Means
a browser-only live operation ran during a server render
Typical cause
a useMutation() call reached from a page body. A server render has no socket and no page store, and a dropped write would look exactly like one that happened, so it refuses rather than queues
Fix
move the call into an island's event handler (x g island <route-dir> --at <route-dir>). Guarding it with hasPageSocket() is not a fix: on the server that answers false forever, and the budgets step reports it as X_LIVE_ROUTE_NO_ISLAND