fix(navigation): make BaseViewModel setState an atomic compare-and-set#1104
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Events are dispatched from multiple threads — the UI thread and background flows
on defaultDispatcher. The old `_stateFlow.value = _stateFlow.value.update()` is a
non-atomic read-modify-write: concurrent reducers can derive from the same
snapshot and clobber each other, silently dropping one event's state change.
Use MutableStateFlow.update {} so the reducer retries against the latest value.
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type: fix
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Problem
BaseViewModel.setStatedid a non-atomic read-modify-write:Events are dispatched from multiple threads — the UI thread and background flows on
defaultDispatcher. Two concurrent reducers can read the same snapshot and clobber each other, silently dropping one event's state change.Fix
Use
MutableStateFlow.update {}, which applies the reducer in a compare-and-set loop and retries against the latest value:_stateFlow.update(update)