fix: filter input not reset on clear filter

[jajugoguma]

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Description

Fixed an issue where the input element of a filter was not initialized when cleared without applying the filter.

Unlike the data in the store, the filterLayerState is not observable. However, the TOAST UI Grid does not unfilter when no filter is applied. After all, the filter in the data does not change, so resetting the filterLayeState does not trigger a re-render.

To properly reflect a resetting filterLayerState, I've changed it to call a notify function to notify that the store has changed, causing a re-render.

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