The new-session row's agents now go through _runModeAvailableForCase (session-ui.js), the rule extracted from _refreshRunModeAvailability, for the case the row launches in: a Docker case offers what its container has (live probe, else availableModes, else ungated), so a container-only Run mode is offered and is the row's default again.
The default is resolved per render (pick, else the Run button's mode, else the first offered), so a query that moves the row to another case starts on the Run mode when that case offers it.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>