chore: delete dead code approved from the PR #166 sweep

Three items the multi-agent sweep flagged, now removed with user
approval (§8 for the solitaire_sync changes):

- WinCascadePlugin: never registered; handle_win_cascade in
  AnimationPlugin is the live win cascade and builds its own targets.
  Its now-orphaned helpers (win_scatter_targets, cascade_delay,
  WIN_CASCADE_INTERVAL_SECS) had no callers outside their own tests
  and go with it.
- SyncCompleteEvent: written by the pull-completion system, zero
  readers — UI reads SyncStatusResource instead.
- solitaire_sync::ApiError: unused by client and server; the merge_at
  crate-root re-export goes too (merge::merge_at stays for the merge
  module's own use).

ARCHITECTURE.md updated to match.

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

ARCHITECTURE.md

@@ -145,7 +145,6 @@ Shared API contract types imported by both the game client (`solitaire_data`) an
 Owns:
 - `SyncPayload`, `SyncResponse`, `ConflictReport`
 - `ChallengeGoal`, `LeaderboardEntry`
-- `ApiError` enum
 - Merge logic (pure functions, no I/O)
 
 ### `solitaire_data`
@@ -257,7 +256,7 @@ solitaire_sync::merge(local, remote)
     │
     ▼
 Write merged result to disk
-    │  fires SyncCompleteEvent
+    │
     ▼
 Bevy main thread reads updated StatsResource
 ```
@@ -377,7 +376,6 @@ struct StateChangedEvent;
 struct CardFlippedEvent(u32);
 struct GameWonEvent { score: i32, time_seconds: u64 }
 struct AchievementUnlockedEvent(AchievementRecord);
-struct SyncCompleteEvent(Result<SyncResponse, String>);
 ```
 
 ### Layout System

solitaire_engine/src/card_animation/animation.rs

@@ -201,27 +201,6 @@ pub(crate) fn advance_card_animations(
     }
 }
 
-// ---------------------------------------------------------------------------
-// Win cascade
-// ---------------------------------------------------------------------------
-
-/// Win-cascade scatter targets — 8 points beyond the window edges.
-///
-/// Scaled by `radius` (pass `layout.card_size.x * 8.0` for a good result).
-pub fn win_scatter_targets(radius: f32) -> [Vec2; 8] {
-    let r = radius;
-    [
-        Vec2::new(r, r),
-        Vec2::new(-r, r),
-        Vec2::new(r, -r),
-        Vec2::new(-r, -r),
-        Vec2::new(0.0, r),
-        Vec2::new(0.0, -r),
-        Vec2::new(r, 0.0),
-        Vec2::new(-r, 0.0),
-    ]
-}
-
 // ---------------------------------------------------------------------------
 // Tests
 // ---------------------------------------------------------------------------
@@ -305,20 +284,4 @@ mod tests {
         assert!((anim.z_lift - 12.0).abs() < 1e-6);
     }
 
-    #[test]
-    fn win_scatter_has_eight_targets() {
-        let targets = win_scatter_targets(800.0);
-        assert_eq!(targets.len(), 8);
-    }
-
-    #[test]
-    fn win_scatter_targets_are_off_center() {
-        for t in win_scatter_targets(400.0) {
-            let dist = t.length();
-            assert!(
-                dist > 100.0,
-                "scatter target should be well off-center: {t:?}"
-            );
-        }
-    }
 }

solitaire_engine/src/card_animation/mod.rs

@@ -31,16 +31,6 @@
 //! ));
 //! ```
 //!
-//! # Win cascade with `Expressive` curve
-//!
-//! The existing `AnimationPlugin` drives the win cascade with `CardAnim`
-//! (linear). To use the curve-based cascade instead, disable
-//! `handle_win_cascade` in `AnimationPlugin` and register `WinCascadePlugin`
-//! (declared below) which uses `CardAnimation` + `MotionCurve::Expressive`.
-//!
-//! They **must not both be active** — both write to `Transform` on the same
-//! 52 entities and will race.
-//!
 //! # Coexistence rules
 //!
 //! | Condition | Safe? |
@@ -58,24 +48,21 @@ pub mod interaction;
 pub mod timing;
 pub mod tuning;
 
-pub use animation::{CardAnimation, win_scatter_targets};
+pub use animation::CardAnimation;
 pub use chain::AnimationChain;
 pub use curves::{MotionCurve, sample_curve};
 pub use diagnostics::{FrameTimeDiagnostics, WINDOW_SIZE as DIAG_WINDOW_SIZE};
 pub use interaction::{BufferedInput, HoverState, InputBuffer};
 pub use timing::{
-    DEAL_INTERVAL_SECS, MAX_DURATION_SECS, MIN_DURATION_SECS, WIN_CASCADE_INTERVAL_SECS,
-    cascade_delay, compute_duration, micro_vary,
+    DEAL_INTERVAL_SECS, MAX_DURATION_SECS, MIN_DURATION_SECS, compute_duration, micro_vary,
 };
 pub use tuning::{AnimationTuning, InputPlatform};
 
 use bevy::prelude::*;
 use bevy::window::RequestRedraw;
 
-use crate::card_plugin::CardEntity;
 use crate::events::{DrawRequestEvent, GameWonEvent, MoveRequestEvent, UndoRequestEvent};
 use crate::game_plugin::GameMutation;
-use crate::layout::LayoutResource;
 use crate::resources::DragState;
 
 use animation::advance_card_animations;
@@ -144,63 +131,6 @@ impl Plugin for CardAnimationPlugin {
     }
 }
 
-// ---------------------------------------------------------------------------
-// Optional: win cascade with Expressive curve
-// ---------------------------------------------------------------------------
-
-/// Optional plugin that replaces the linear win cascade in `AnimationPlugin`
-/// with an `Expressive`-curve cascade.
-///
-/// **Do not register this alongside `AnimationPlugin`'s win cascade** — they
-/// will race on the same card entities. To use this plugin, prevent
-/// `AnimationPlugin` from handling `GameWonEvent` (or remove it and manage
-/// win toasts manually).
-pub struct WinCascadePlugin;
-
-impl Plugin for WinCascadePlugin {
-    fn build(&self, app: &mut App) {
-        app.add_systems(Update, trigger_expressive_win_cascade.after(GameMutation));
-    }
-}
-
-/// Inserts `CardAnimation` (Expressive curve) on every card when `GameWonEvent` fires.
-///
-/// Cards scatter to 8 off-screen positions with per-card stagger. The z-lift
-/// creates a "burst" effect as cards fly outward.
-fn trigger_expressive_win_cascade(
-    mut events: MessageReader<GameWonEvent>,
-    cards: Query<(Entity, &Transform), With<CardEntity>>,
-    layout: Option<Res<LayoutResource>>,
-    mut commands: Commands,
-) {
-    if events.read().next().is_none() {
-        return;
-    }
-
-    let radius = layout.as_ref().map_or(800.0, |l| l.0.card_size.x * 8.0);
-
-    let targets = win_scatter_targets(radius);
-
-    for (index, (entity, transform)) in cards.iter().enumerate() {
-        let start_xy = transform.translation.truncate();
-        let start_z = transform.translation.z;
-        let target = targets[index % targets.len()];
-
-        commands.entity(entity).insert(
-            CardAnimation::slide(
-                start_xy,
-                start_z,
-                target,
-                start_z + 60.0,
-                MotionCurve::Expressive,
-            )
-            .with_delay(cascade_delay(index, WIN_CASCADE_INTERVAL_SECS))
-            .with_duration(0.65)
-            .with_z_lift(25.0),
-        );
-    }
-}
-
 // ---------------------------------------------------------------------------
 // Tests
 // ---------------------------------------------------------------------------
@@ -433,19 +363,4 @@ mod tests {
         let state = HoverState::default();
         assert!(state.entity.is_none());
     }
-
-    #[test]
-    fn win_scatter_produces_eight_distinct_points() {
-        let targets = win_scatter_targets(600.0);
-        assert_eq!(targets.len(), 8);
-        // All must be different.
-        for i in 0..8 {
-            for j in (i + 1)..8 {
-                assert_ne!(
-                    targets[i], targets[j],
-                    "scatter targets {i} and {j} must be distinct"
-                );
-            }
-        }
-    }
 }

solitaire_engine/src/card_animation/timing.rs

@@ -49,17 +49,6 @@ pub fn micro_vary(duration: f32, entity_index: u32) -> f32 {
     duration * (1.0 + variation)
 }
 
-/// Returns the pre-animation delay for card at `index` in a staggered cascade.
-///
-/// `delay = index × interval_secs`.
-#[inline]
-pub fn cascade_delay(index: usize, interval_secs: f32) -> f32 {
-    index as f32 * interval_secs
-}
-
-/// Recommended per-card interval for the win cascade (Normal speed).
-pub const WIN_CASCADE_INTERVAL_SECS: f32 = 0.018;
-
 /// Recommended per-card interval for deal animations (Normal speed).
 pub const DEAL_INTERVAL_SECS: f32 = 0.022;
 
@@ -138,21 +127,4 @@ mod tests {
         );
     }
 
-    #[test]
-    fn cascade_delay_zero_index_is_zero() {
-        assert_eq!(cascade_delay(0, 0.018), 0.0);
-    }
-
-    #[test]
-    fn cascade_delay_scales_linearly() {
-        let interval = 0.018;
-        for i in 0..52usize {
-            let expected = i as f32 * interval;
-            let actual = cascade_delay(i, interval);
-            assert!(
-                (actual - expected).abs() < 1e-6,
-                "cascade_delay({i}) = {actual}, expected {expected}"
-            );
-        }
-    }
 }

solitaire_engine/src/events.rs

@@ -5,7 +5,6 @@ use solitaire_core::KlondikePile;
 use solitaire_core::game_state::GameMode;
 use solitaire_core::{Card, Suit};
 use solitaire_data::AchievementRecord;
-use solitaire_sync::SyncResponse;
 
 /// Request to move `count` cards from `from` to `to`. Fired by input systems,
 /// consumed by `GamePlugin`.
@@ -248,16 +247,6 @@ pub struct ToggleLeaderboardRequestEvent;
 #[derive(Message, Debug, Clone, Copy, Default)]
 pub struct ToggleHomeRequestEvent;
 
-/// Fired by `SyncPlugin` after a pull task resolves and the merged result has
-/// been persisted to disk. `Ok(SyncResponse)` carries the merged payload plus
-/// any `ConflictReport`s the merge produced. `Err(String)` carries a
-/// human-readable failure message (network, auth, serialization, etc.).
-///
-/// UI systems listen for this to refresh views without polling
-/// `SyncStatusResource`. See [ARCHITECTURE.md §4](../../ARCHITECTURE.md).
-#[derive(Message, Debug, Clone)]
-pub struct SyncCompleteEvent(pub Result<SyncResponse, String>);
-
 /// Generic informational toast message. Any system can fire this to display
 /// a short string to the player, e.g. "Locked — reach level 5".
 #[derive(Message, Debug, Clone)]

solitaire_engine/src/lib.rs

@@ -83,9 +83,8 @@ pub use avatar_plugin::{AvatarFetchEvent, AvatarPlugin, AvatarResource};
 pub use card_animation::{
     AnimationChain, AnimationTuning, BufferedInput, CardAnimation, CardAnimationPlugin,
     DEAL_INTERVAL_SECS, DIAG_WINDOW_SIZE, FrameTimeDiagnostics, HoverState, InputBuffer,
-    InputPlatform, MAX_DURATION_SECS, MIN_DURATION_SECS, MotionCurve, WIN_CASCADE_INTERVAL_SECS,
-    WinCascadePlugin, cascade_delay, compute_duration, micro_vary, sample_curve,
-    win_scatter_targets,
+    InputPlatform, MAX_DURATION_SECS, MIN_DURATION_SECS, MotionCurve, compute_duration,
+    micro_vary, sample_curve,
 };
 pub use card_plugin::{
     CardEntity, CardImageSet, CardLabel, CardPlugin, HintHighlight, HintHighlightTimer,
@@ -107,7 +106,7 @@ pub use events::{
     HintVisualEvent, InfoToastEvent, ManualSyncRequestEvent, MoveRejectedEvent, MoveRequestEvent,
     NewGameRequestEvent, PauseRequestEvent, StartChallengeRequestEvent,
     StartDailyChallengeRequestEvent, StartDifficultyRequestEvent, StartPlayBySeedRequestEvent,
-    StartTimeAttackRequestEvent, StartZenRequestEvent, StateChangedEvent, SyncCompleteEvent,
+    StartTimeAttackRequestEvent, StartZenRequestEvent, StateChangedEvent,
     ToggleAchievementsRequestEvent, ToggleLeaderboardRequestEvent, ToggleProfileRequestEvent,
     ToggleSettingsRequestEvent, ToggleStatsRequestEvent, UndoRequestEvent, WinStreakMilestoneEvent,
     XpAwardedEvent,

solitaire_engine/src/sync_plugin.rs

@@ -22,12 +22,11 @@ use solitaire_data::{
     AchievementRecord, PlayerProgress, Replay, StatsSnapshot, SyncError, SyncProvider,
     save_achievements_to, save_progress_to, save_replay_history_to, save_stats_to,
 };
-use solitaire_sync::{SyncPayload, SyncResponse, merge};
+use solitaire_sync::{SyncPayload, merge};
 
 use crate::achievement_plugin::{AchievementsResource, AchievementsStoragePath};
 use crate::events::{
-    GameWonEvent, ManualSyncRequestEvent, SyncCompleteEvent, SyncConfigureRequestEvent,
-    WarningToastEvent,
+    GameWonEvent, ManualSyncRequestEvent, SyncConfigureRequestEvent, WarningToastEvent,
 };
 use crate::game_plugin::RecordingReplay;
 use crate::progress_plugin::{ProgressResource, ProgressStoragePath};
@@ -108,7 +107,6 @@ impl Plugin for SyncPlugin {
             .init_resource::<PullTask>()
             .init_resource::<PendingReplayUpload>()
             .add_message::<ManualSyncRequestEvent>()
-            .add_message::<SyncCompleteEvent>()
             .add_message::<SyncConfigureRequestEvent>()
             .add_message::<WarningToastEvent>();
 
@@ -198,7 +196,6 @@ fn poll_pull_result(
     achievements_path: Res<AchievementsStoragePath>,
     mut progress: ResMut<ProgressResource>,
     progress_path: Res<ProgressStoragePath>,
-    mut complete_writer: MessageWriter<SyncCompleteEvent>,
     mut configure_sync: MessageWriter<SyncConfigureRequestEvent>,
     mut warning_toast: MessageWriter<WarningToastEvent>,
 ) {
@@ -213,7 +210,7 @@ fn poll_pull_result(
     match result {
         Ok(remote) => {
             let local = build_payload(&stats.0, &achievements.0, &progress.0);
-            let (merged, conflicts) = merge(&local, &remote);
+            let (merged, _conflicts) = merge(&local, &remote);
 
             // Persist merged state atomically.
             if let Some(p) = &stats_path.0
@@ -233,17 +230,10 @@ fn poll_pull_result(
             }
 
             // Update in-world resources.
-            let now = Utc::now();
-            stats.0 = merged.stats.clone();
-            achievements.0 = merged.achievements.clone();
-            progress.0 = merged.progress.clone();
-            status.0 = SyncStatus::LastSynced(now);
-
-            complete_writer.write(SyncCompleteEvent(Ok(SyncResponse {
-                merged,
-                server_time: now,
-                conflicts,
-            })));
+            stats.0 = merged.stats;
+            achievements.0 = merged.achievements;
+            progress.0 = merged.progress;
+            status.0 = SyncStatus::LastSynced(Utc::now());
         }
         Err(SyncError::UnsupportedPlatform) => {
             // No backend configured — not an error, just leave status as Idle.
@@ -266,8 +256,7 @@ fn poll_pull_result(
             if matches!(e, SyncError::Auth(_)) {
                 configure_sync.write(SyncConfigureRequestEvent);
             }
-            status.0 = SyncStatus::Error(msg.clone());
-            complete_writer.write(SyncCompleteEvent(Err(msg)));
+            status.0 = SyncStatus::Error(msg);
         }
     }
 }

solitaire_sync/src/lib.rs

@@ -13,7 +13,7 @@ pub mod stats;
 pub mod theme_store;
 
 pub use achievements::AchievementRecord;
-pub use merge::{merge, merge_at};
+pub use merge::merge;
 pub use progress::{PlayerProgress, level_for_xp};
 pub use stats::StatsSnapshot;
 pub use theme_store::{ThemeCatalogEntry, ThemeCatalogResponse};
@@ -98,30 +98,3 @@ pub struct LeaderboardEntry {
     /// When this entry was last recorded.
     pub recorded_at: DateTime<Utc>,
 }
-
-// ---------------------------------------------------------------------------
-// Error types
-// ---------------------------------------------------------------------------
-
-/// Errors returned by the sync server in `application/json` error bodies.
-#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, thiserror::Error)]
-pub enum ApiError {
-    /// The request could not be authenticated (missing or invalid JWT).
-    #[error("unauthorized")]
-    Unauthorized,
-    /// The supplied credentials were incorrect.
-    #[error("invalid credentials")]
-    InvalidCredentials,
-    /// A username that was requested for registration is already taken.
-    #[error("username already taken")]
-    UsernameTaken,
-    /// The request payload was too large (> 1 MB).
-    #[error("payload too large")]
-    PayloadTooLarge,
-    /// The request body could not be parsed.
-    #[error("bad request: {0}")]
-    BadRequest(String),
-    /// An unexpected server-side error occurred.
-    #[error("internal server error")]
-    Internal,
-}