refactor(engine): ambiguity burn-down batch 4 — zero ambiguities, gate enforced

Clears the final 47 pairs and turns the ratchet into a hard gate
(AMBIGUITY_BASELINE = 0, assert_eq):

- HudButtons: the 14 HUD button/popover handlers run as one chain,
  before ui_focus::FocusKeys — Esc/keyboard consumption order is now
  defined (restore prompt → buttons/popovers → focus navigation →
  settings toggle) instead of scheduler-dependent.
- HUD text updaters (update_hud, update_selection_hud,
  update_won_previously) chained, in UiTextFx, after the new
  AutoComplete set (update_hud reads AutoCompleteState).
- restore_hud_on_modal → apply_hud_visibility chained before
  UpdateOnResize: HudVisibility writes, application, and the layout
  read happen in a fixed order.
- New writer sets UndoRequestWriters / InfoToastWriters (same
  self-ambiguous pattern as NewGameRequestWriters).
- Logic-before-paint: check_no_moves and the AutoComplete chain order
  before BoardVisuals; SettingsMutation after UpdateOnResize.
- MarkerVisuals set wraps the table painter chain; chrome fx declare
  disjointness from it.
- update_hud_typography after BoardVisuals; avatar/settings-toggle
  interaction handlers declared disjoint from HudButtons.

302 → 198 → 171 → 47 → 0 in four batches, one day. New systems now
fail CI unless they declare their ordering or their disjointness.

Closes #143

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

solitaire_engine/src/hud_plugin/mod.rs

@@ -154,6 +154,13 @@ pub struct HudColumn;
 #[derive(Component, Debug)]
 pub struct HudActionBar;
 
+/// Set wrapping the chained HUD button/popover interaction systems. Other
+/// keyboard consumers order themselves around it (e.g.
+/// [`crate::ui_focus::FocusKeys`] runs after) so input-consumption order is
+/// deterministic (#143).
+#[derive(bevy::ecs::schedule::SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
+pub struct HudButtons;
+
 /// Marker on the text node inside each touch-layout action-bar button.
 /// Used by `resize_action_bar_labels` to update font size on window resize.
 #[derive(Component, Debug)]
@@ -468,31 +475,56 @@ impl Plugin for HudPlugin {
             // defensively so the HUD plugin works standalone in tests.
             .add_message::<WindowResized>()
             .add_systems(Startup, (spawn_hud_band, spawn_hud, spawn_action_buttons, spawn_hud_avatar))
-            .add_systems(Update, update_hud.after(GameMutation))
+            // HUD text updaters run as one deterministic chain (they write
+            // disjoint Text nodes, but Bevy can't prove it); update_hud also
+            // reads AutoCompleteState, so the chain sits after the
+            // auto-complete detect/drive chain (#143).
             .add_systems(
                 Update,
-                apply_hud_visibility.before(LayoutSystem::UpdateOnResize),
+                (
+                    update_hud,
+                    update_selection_hud.run_if(
+                        resource_exists_and_changed::<SelectionState>
+                            .or(resource_exists_and_changed::<GameStateResource>),
+                    ),
+                    update_won_previously,
+                )
+                    .chain()
+                    .after(GameMutation)
+                    .after(crate::auto_complete_plugin::AutoComplete)
+                    .in_set(UiTextFx)
+                    .ambiguous_with(UiTextFx),
+            )
+            // HUD chrome visibility: modal-restore writes HudVisibility, the
+            // applier consumes it, and the layout recompute reads it — a
+            // fixed chain instead of three racing systems (#143).
+            .add_systems(
+                Update,
+                (restore_hud_on_modal, apply_hud_visibility)
+                    .chain()
+                    .before(LayoutSystem::UpdateOnResize),
             )
-            .add_systems(Update, restore_hud_on_modal)
             .add_systems(
                 Update,
                 (
                     update_hud_avatar.after(crate::settings_plugin::SettingsMutation),
-                    handle_avatar_button,
+                    handle_avatar_button.ambiguous_with(HudButtons),
                 ),
             )
-            .add_systems(Update, update_won_previously.after(GameMutation))
-            .add_systems(Update, announce_auto_complete.after(GameMutation))
             .add_systems(
                 Update,
-                update_selection_hud
+                announce_auto_complete
                     .after(GameMutation)
-                    .run_if(
-                        resource_exists_and_changed::<SelectionState>
-                            .or(resource_exists_and_changed::<GameStateResource>),
-                    ),
+                    .after(crate::auto_complete_plugin::AutoComplete)
+                    .in_set(crate::game_plugin::InfoToastWriters)
+                    .ambiguous_with(crate::game_plugin::InfoToastWriters),
+            )
+            // Typography rescale touches HUD TextFont only, but orders after
+            // the board painters that resize card/label text (#143).
+            .add_systems(
+                Update,
+                update_hud_typography.after(crate::card_plugin::BoardVisuals),
             )
-            .add_systems(Update, update_hud_typography)
             .add_systems(
                 Update,
                 (
@@ -521,10 +553,16 @@ impl Plugin for HudPlugin {
                     handle_new_game_button
                         .in_set(NewGameRequestWriters)
                         .ambiguous_with(NewGameRequestWriters),
-                    handle_undo_button,
+                    handle_undo_button
+                        .in_set(crate::game_plugin::UndoRequestWriters)
+                        .ambiguous_with(crate::game_plugin::UndoRequestWriters)
+                        .before(GameMutation),
                     handle_pause_button,
                     handle_help_button,
-                    handle_hint_button.after(GameMutation),
+                    handle_hint_button
+                        .after(GameMutation)
+                        .in_set(crate::game_plugin::InfoToastWriters)
+                        .ambiguous_with(crate::game_plugin::InfoToastWriters),
                     handle_modes_button,
                     handle_mode_option_click
                         .in_set(NewGameRequestWriters)
@@ -536,7 +574,10 @@ impl Plugin for HudPlugin {
                     handle_menu_backdrop_click,
                     close_menu_popover_on_escape,
                     paint_action_buttons,
-                ),
+                )
+                    .chain()
+                    .in_set(HudButtons)
+                    .before(crate::ui_focus::FocusKeys),
             )
             // Fade lives in `Last` so it always overrides whatever the
             // hover/paint pass set on `BackgroundColor` this frame.