watch method
Returns a reactive ReadonlySignal tracking the boolean state of flagName.
If the flag does not already exist, it is lazily created and initialized with defaultValue.
Reading .value inside a Live, Show, or effect establishes a reactive dependency,
causing the observing block to re-execute whenever the flag changes.
final betaSignal = features.watch('beta_chat');
Live(() => betaSignal.value ? ChatWidget() : DisabledWidget())
Implementation
ReadonlySignal<bool> watch(String flagName, {bool defaultValue = false}) {
return _getOrCreateSignal(flagName, defaultValue: defaultValue);
}