fix(web): clean up wasm32 build warnings and wire /play route to Bevy canvas

- solitaire_data/sync_client.rs: fix SyncPayload/SyncResponse import split
  (SyncResponse is needed by LocalOnlyProvider which compiles on wasm32)
- solitaire_engine/assets/sources.rs: cfg-gate AssetApp/AssetSourceBuilder
  imports (only used in the non-wasm FileAssetReader block)
- solitaire_engine/auto_complete_plugin.rs: cfg-gate AUTO_COMPLETE_CHIME_VOLUME
- solitaire_engine/daily_challenge_plugin.rs: cfg-gate Task/AsyncComputeTaskPool
  imports and DailyChallengeTask struct (server fetch systems are non-wasm only)
- solitaire_engine/resources.rs: cfg-gate std::sync::Arc (TokioRuntimeResource
  is non-wasm only)
- solitaire_engine/settings_plugin.rs: cfg-gate ScanThemes variant, pill_button,
  and their match arms; fix refresh_registry import placement
- solitaire_server/src/lib.rs: point /play route at play.html (Bevy canvas);
  keep /play-classic serving game.html during transition period
- build_wasm.sh: add --no-typescript to wasm-bindgen call for canvas build
- solitaire_server/web/pkg: add canvas.js + canvas_bg.wasm build artifacts

wasm32 build and native clippy --workspace -D warnings both clean.

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

solitaire_engine/src/daily_challenge_plugin.rs

@@ -13,9 +13,11 @@
 
 use bevy::input::ButtonInput;
 use bevy::prelude::*;
-use bevy::tasks::{AsyncComputeTaskPool, Task, futures_lite::future};
 use chrono::{DateTime, Duration, Local, NaiveDate, Utc};
 use solitaire_data::{daily_seed_for, save_progress_to};
+#[cfg(not(target_arch = "wasm32"))]
+use bevy::tasks::{AsyncComputeTaskPool, Task, futures_lite::future};
+#[cfg(not(target_arch = "wasm32"))]
 use solitaire_sync::ChallengeGoal;
 
 use crate::events::{
@@ -78,8 +80,13 @@ pub struct DailyChallengeCompletedEvent {
 /// Holds the in-flight server challenge fetch so the result can be polled
 /// each frame without blocking the main thread.
 #[derive(Resource, Default)]
+#[cfg(not(target_arch = "wasm32"))]
 struct DailyChallengeTask(Option<Task<Option<ChallengeGoal>>>);
 
+#[derive(Resource, Default)]
+#[cfg(target_arch = "wasm32")]
+struct DailyChallengeTask;
+
 /// Tracks which `DailyChallengeResource::date` the expiry-warning toast has
 /// already fired for, so the toast spawns at most once per day.
 ///