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_data/src/sync_client.rs

@@ -12,7 +12,9 @@
 //! without matching on [`SyncBackend`] anywhere else in the codebase.
 
 use async_trait::async_trait;
-use solitaire_sync::{ChallengeGoal, LeaderboardEntry, SyncPayload, SyncResponse};
+use solitaire_sync::{SyncPayload, SyncResponse};
+#[cfg(not(target_arch = "wasm32"))]
+use solitaire_sync::{ChallengeGoal, LeaderboardEntry};
 
 use crate::{SyncError, SyncProvider};