refactor: persist replay/save moves as KlondikeInstruction, not pile coords (#89)

Pile-position types (Tableau, Foundation, KlondikePile, KlondikePileStack)
are runtime-only and have no serde upstream. Per Rhys's guidance, the
persistence layer now stores the moves (KlondikeInstruction) rather than
board coordinates, decoding back to runtime pile positions on demand.

Core / data:
- game_state: instruction_history() -> Vec<KlondikeInstruction>; add
  instruction_to_piles() and apply_instruction(); drop AnyInstruction.
- klondike_adapter: delete the entire Saved* serde mirror section
  (SavedTableau/Foundation/SkipCards/KlondikePile/TableauStack/
  KlondikePileStack/DstFoundation/DstTableau/SavedInstruction).
- replay: drop the bespoke ReplayMove serde mirror; Replay.moves is now
  Vec<KlondikeInstruction>; REPLAY_SCHEMA_VERSION 2 -> 3.
- storage: game_state save format v3 rejected (v4/v5 only).

Engine / wasm consumers:
- record via KlondikeInstruction (stock click = RotateStock).
- playback decodes each instruction to (from, to, count) against the
  live state via instruction_to_piles, then fires the canonical event;
  undecodable instructions are skipped with a warning, never panic.
- remove all use solitaire_data::ReplayMove and Saved* imports.

Workspace check, clippy -D warnings, and the full test suite all pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

solitaire_data/src/storage.rs

@@ -583,24 +583,16 @@ mod tests {
         );
     }
 
-    /// A schema v3 save (instruction history using u8 indices) must load
-    /// successfully and be transparently migrated to schema v4.
-    ///
-    /// This verifies the `AnyInstruction` untagged deserialization migration
-    /// path. v3 files with `RotateStock` (unit variant, format-identical in
-    /// v3 and v4) load correctly and report `schema_version == 4` after load.
-    /// The `SavedInstruction` boundary tests in `proptest_tests.rs` cover the
-    /// u8-to-named conversion for `DstFoundation` / `DstTableau` indices.
+    /// A schema v3 save (instruction history using the old u8-index mirror
+    /// types) is no longer loadable. The legacy migration path was dropped,
+    /// so any file claiming `schema_version: 3` must be rejected and the
+    /// player started on a fresh game.
     #[test]
-    fn game_state_v3_migrates_to_v4() {
-        use solitaire_core::game_state::GameState;
-
-        let path = gs_path("v3_migrate");
+    fn game_state_v3_is_rejected() {
+        let path = gs_path("v3_reject");
         let _ = fs::remove_file(&path);
 
         // Hand-crafted schema v3 JSON: one RotateStock (draw) instruction.
-        // RotateStock serialises as the string "RotateStock" in both v3 and v4,
-        // so this exercises the schema version acceptance code path.
         let v3_json = r#"{
             "draw_mode": "DrawOne",
             "mode": "Classic",
@@ -615,13 +607,12 @@ mod tests {
         }"#;
         fs::write(&path, v3_json).expect("write v3 fixture");
 
-        let loaded = load_game_state_from(&path)
-            .expect("schema v3 must be accepted and migrated to v4");
+        assert!(
+            load_game_state_from(&path).is_none(),
+            "schema v3 must be rejected (no migration path)",
+        );
 
-        // The loaded game should match a fresh game that had one draw applied.
-        let mut expected = GameState::new(42, DrawStockConfig::DrawOne);
-        expected.draw().expect("draw must succeed on a fresh game");
-        assert_eq!(loaded, expected, "migrated v3 game state must match equivalent v4 state");
+        let _ = fs::remove_file(&path);
     }
 
     /// Schema v2 stored raw pile arrays and undo snapshots (no instruction