MessageSearchBar
fun MessageSearchBar(query: String, onQueryChange: (String) -> Unit, onClose: () -> Unit, resultCount: Int, currentIndex: Int = 0, onPrevious: () -> Unit = {}, onNext: () -> Unit = {}, modifier: Modifier = Modifier)(source)
M3 contextual search bar that replaces the standard MessageTopBar when search is active. Follows the M3 "find in page" pattern: back arrow + text field + "X of Y" counter + prev/next arrows + clear.
This uses TopAppBar rather than SearchBar because we're filtering within an existing conversation (contextual search), not performing primary app-level navigation search.