fix(android): gate Monitor/PrimaryMonitor/PrimaryWindow imports to non-Android

These three bevy::window types are only referenced by
apply_smart_default_window_size, which is already cfg(not(android)).
The unconditional import triggered -D unused-imports on the Android
cross-compile. Split into a separate cfg-gated use statement.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

solitaire_app/src/lib.rs

@@ -18,9 +18,9 @@ use std::io::Write;
 use std::time::{SystemTime, UNIX_EPOCH};
 
 use bevy::prelude::*;
-use bevy::window::{
-    Monitor, MonitorSelection, PresentMode, PrimaryMonitor, PrimaryWindow, WindowPosition,
-};
+use bevy::window::{MonitorSelection, PresentMode, WindowPosition};
+#[cfg(not(target_os = "android"))]
+use bevy::window::{Monitor, PrimaryMonitor, PrimaryWindow};
 #[cfg(not(target_os = "android"))]
 use bevy::winit::WinitWindows;
 use solitaire_data::{load_settings_from, provider_for_backend, settings_file_path, Settings};