Bind reachable navigation-compose @Composable methods; document animation-surface blocker

[Copilot]

Xamarin.AndroidX.Navigation.Compose shipped its *Kt wrappers (NavHostKt, NavGraphBuilderKt, DialogHostKt, NavHostControllerKt, NavBackStackEntryProviderKt) as empty classes, making the entire @Composable navigation surface unreachable from C#.

Root cause

The generator silently drops any Java method whose parameter/return types can't be resolved to a managed type (warning BG8605). The dropped members reference types that are intentionally unbound repo-wide:

• androidx.compose.animation.* — AnimatedContentScope, AnimatedContentTransitionScope, EnterTransition, ExitTransition, SizeTransform. The animation-android binding's Metadata.xml is just <remove-node path="/api/package" />, so the package produces zero C# types.
• androidx.compose.runtime.saveable.SaveableStateHolder, androidx.compose.runtime.snapshots.SnapshotStateList.

This is independent of inline-class mangling (java-interop#1440) and is not a navigation-compose Metadata.xml removal (it has none). Methods whose signatures resolve fully are bound correctly; methods touching the animation/saveable types are filtered.

Changes

• PublicAPI/PublicAPI.Unshipped.txt — refreshed the stale baseline to capture the now-bindable subset:
  • DialogHostKt.DialogHost(DialogNavigator, …)
  • NavGraphBuilderKt.Dialog(…) (string + KClass overloads)
  • NavHostControllerKt.RememberNavController(Navigator[], …)
  • NavHostControllerKt.CurrentBackStackEntryAsState(NavController, …)
  • constructors for DialogNavigator.Destination and DialogNavigatorDestinationBuilder
• config.json — bump navigation-compose and navigation-compose-android nugetVersion 2.9.8 → 2.9.8.1.
• published-namespaces.txt — no change required; AndroidX.Navigation.Compose is already published.

Still unbound (out of scope)

NavHost, NavGraphBuilder.composable, NavGraphBuilder.navigation, and NavBackStackEntry.LocalOwnersProvider remain empty — they cannot bind until androidx.compose.animation (and compose.runtime.saveable) are themselves bound. That is a large, separate cross-library effort: the package is deliberately stripped via remove-node, and an add-node shim is not viable because the generated C# would reference types that don't exist. Tracked as the real blocker behind this Compose surface.