On some setups the localStorage quota is exhausted; the bare setItem
call throws an unhandled DOMException that breaks model selection and
prevents the chat UI from loading.
Wrap both call-sites (boot.js model-select onChange, onboarding.js
_saveOnboardingDefaults) in try/catch so the error is logged to the
console as a warning instead of surfacing as a fatal exception.
Fixes: 'Failed to execute setItem on Storage: Setting the value of
hermes-webui-model exceeded the quota.'