fix(web): rebuild Bevy canvas WASM; add SolitaireGame interactive API

Grey screen fix (canvas_bg.wasm):
- Rebuilt Bevy WASM from refactored solitaire_core that removes the
  per-game KlondikeAdapter field from GameState. The old binary was
  built with wasm-opt -Oz; the large adapter allocation pattern appears
  to trigger an over-aggressive wasm-opt optimisation that corrupts
  Bevy's render pipeline, causing a permanent grey screen on /play.
- build_wasm.sh: change wasm-opt -Oz → -O2. Speed-optimised level avoids
  the size-focused transforms that miscompile Bevy's deep render stacks.

solitaire_core refactoring:
- game_state.rs: remove adapter: KlondikeAdapter field; use static
  KlondikeAdapter::config_for() instead of a per-instance allocation.
  Gate test_pile_state behind #[cfg(feature = "test-support")] so
  production builds carry no test-only heap state.
  Add instruction_history() public accessor (delegates to saved_moves()).
- card.rs: add Card::new(), face_up(), face_down() const constructors
  for more ergonomic test and wasm code.
- pile.rs, solver.rs: cargo fmt.

solitaire_wasm interactive API:
- lib.rs: add SolitaireGame wasm-bindgen struct with draw(), move_cards(),
  undo(), auto_complete_step(), serialize(), from_saved() — the full
  player-action surface used by game.js.
  Add DebugSnapshot, DebugMove, DebugInvariantReport structs and
  debug_snapshot(), debug_legal_moves(), debug_apply_move_json()
  methods for e2e test automation (window.__FERROUS_DEBUG__ bridge).
  Add replay_moves() to export the current game as a Replay v2 payload.
- solitaire_wasm.js + solitaire_wasm_bg.wasm: rebuilt with new API.

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

solitaire_core/src/card.rs

@@ -111,6 +111,28 @@ pub struct Card {
     pub face_up: bool,
 }
 
+impl Card {
+    /// Creates a card with explicit face orientation.
+    pub const fn new(id: u32, suit: Suit, rank: Rank, face_up: bool) -> Self {
+        Self {
+            id,
+            suit,
+            rank,
+            face_up,
+        }
+    }
+
+    /// Creates a face-up card.
+    pub const fn face_up(id: u32, suit: Suit, rank: Rank) -> Self {
+        Self::new(id, suit, rank, true)
+    }
+
+    /// Creates a face-down card.
+    pub const fn face_down(id: u32, suit: Suit, rank: Rank) -> Self {
+        Self::new(id, suit, rank, false)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -166,4 +188,19 @@ mod tests {
         assert!(Suit::Diamonds.is_red() && Suit::Hearts.is_red());
         assert!(Suit::Clubs.is_black() && Suit::Spades.is_black());
     }
+
+    #[test]
+    fn card_constructors_set_fields() {
+        let up = Card::face_up(10, Suit::Spades, Rank::Queen);
+        assert_eq!(up.id, 10);
+        assert_eq!(up.suit, Suit::Spades);
+        assert_eq!(up.rank, Rank::Queen);
+        assert!(up.face_up);
+
+        let down = Card::face_down(11, Suit::Diamonds, Rank::King);
+        assert_eq!(down.id, 11);
+        assert_eq!(down.suit, Suit::Diamonds);
+        assert_eq!(down.rank, Rank::King);
+        assert!(!down.face_up);
+    }
 }