LocalTilesManager

Carries the current screen's TilesManager down the tree, or null outside any screen — provided by MosaicScreen. This is what makes the nested-navigation-graph pattern possible: a custom container tile that hosts its own mini backstack composes its own MosaicScreen(parent = LocalTilesManager.current), so lookups that miss inside the nested tree can recurse upward into the hosting screen's own TilesManager (see NestedNavigationGraph for the built-in example).