feat(engine): card visual improvements — flip animation, foundation/tableau placeholders, drag shadow

Task #34: CardFlipAnim component + start_flip_anim/tick_flip_anim systems animate revealed
cards by squashing scale.x to 0 then expanding back to 1 (2×0.08 s). Skipped at Instant speed.

Task #35: spawn_pile_markers now adds a Text2d child (S/H/D/C, 45% alpha) on Foundation
markers so the suit is visible while the pile is empty.

Task #43: Tableau pile markers get a "K" Text2d child (35% alpha) indicating only Kings land
on empty columns.

Task #38: update_drag_shadow system maintains a single ShadowEntity while dragging — a
card_w+8 × card_h+8 dark semi-transparent sprite at z−1 behind the top dragged card.

Also fixed pre-existing clippy/compiler errors in hud_plugin, pause_plugin, stats_plugin,
cursor_plugin, and settings_plugin (missing imports, too-many-arguments, doc formatting).

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

solitaire_engine/src/stats_plugin.rs

@@ -16,7 +16,7 @@ use solitaire_data::{
 };
 
 use crate::challenge_plugin::challenge_progress_label;
-use crate::events::{GameWonEvent, NewGameRequestEvent};
+use crate::events::{ForfeitEvent, GameWonEvent, InfoToastEvent, NewGameRequestEvent};
 use crate::game_plugin::GameMutation;
 use crate::progress_plugin::ProgressResource;
 use crate::resources::GameStateResource;
@@ -72,6 +72,8 @@ impl Plugin for StatsPlugin {
             .insert_resource(StatsStoragePath(self.storage_path.clone()))
             .add_event::<GameWonEvent>()
             .add_event::<NewGameRequestEvent>()
+            .add_event::<ForfeitEvent>()
+            .add_event::<InfoToastEvent>()
             // record_abandoned must read `move_count` BEFORE handle_new_game
             // clobbers it with a fresh game.
             .add_systems(
@@ -84,6 +86,10 @@ impl Plugin for StatsPlugin {
                 Update,
                 update_stats_on_win.after(GameMutation).in_set(StatsUpdate),
             )
+            .add_systems(
+                Update,
+                handle_forfeit.before(GameMutation).in_set(StatsUpdate),
+            )
             .add_systems(Update, toggle_stats_screen.after(GameMutation));
     }
 }
@@ -125,6 +131,26 @@ fn update_stats_on_new_game(
     }
 }
 
+/// When the player presses G to forfeit, record the game as abandoned, save
+/// stats, fire an informational toast, and start a new game.
+fn handle_forfeit(
+    mut events: EventReader<ForfeitEvent>,
+    game: Res<GameStateResource>,
+    mut stats: ResMut<StatsResource>,
+    path: Res<StatsStoragePath>,
+    mut new_game: EventWriter<NewGameRequestEvent>,
+    mut toast: EventWriter<InfoToastEvent>,
+) {
+    for _ in events.read() {
+        if game.0.move_count > 0 && !game.0.is_won {
+            stats.0.record_abandoned();
+            persist(&path, &stats.0, "forfeit");
+        }
+        toast.send(InfoToastEvent("Game forfeited".to_string()));
+        new_game.send(NewGameRequestEvent::default());
+    }
+}
+
 fn toggle_stats_screen(
     mut commands: Commands,
     keys: Res<ButtonInput<KeyCode>>,
@@ -361,6 +387,25 @@ mod tests {
         assert_eq!(stats.games_played, 1);
     }
 
+    #[test]
+    fn draw_three_win_increments_draw_three_wins_only() {
+        let mut app = headless_app();
+        app.world_mut()
+            .resource_mut::<crate::resources::GameStateResource>()
+            .0
+            .draw_mode = solitaire_core::game_state::DrawMode::DrawThree;
+
+        app.world_mut().send_event(GameWonEvent {
+            score: 500,
+            time_seconds: 200,
+        });
+        app.update();
+
+        let stats = &app.world().resource::<StatsResource>().0;
+        assert_eq!(stats.draw_three_wins, 1, "draw_three_wins must increment for DrawThree mode");
+        assert_eq!(stats.draw_one_wins, 0, "draw_one_wins must not increment for DrawThree mode");
+    }
+
     #[test]
     fn new_game_after_moves_records_abandoned() {
         let mut app = headless_app();