refactor(core): move solver to solitaire_data, DrawMode to klondike_adapter, remove pile/solver/schema_version

- Delete solitaire_core::solver — moved wholesale to solitaire_data::solver (re-exported at crate root)
- Delete solitaire_core::pile — no external users
- Move DrawMode from game_state to klondike_adapter; re-export as solitaire_core::DrawMode
- Remove schema_version field from GameState (redundant — deserializer stamps it from the constant)
- Update all callers across solitaire_data, solitaire_engine, solitaire_assetgen, solitaire_wasm

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

solitaire_data/src/storage.rs

@@ -9,7 +9,7 @@ use std::io;
 use std::path::{Path, PathBuf};
 
 use serde::{Deserialize, Serialize};
-use solitaire_core::game_state::{GAME_STATE_SCHEMA_VERSION, GameState};
+use solitaire_core::game_state::GameState;
 
 use crate::stats::StatsSnapshot;
 
@@ -85,9 +85,6 @@ pub fn game_state_file_path() -> Option<PathBuf> {
 pub fn load_game_state_from(path: &Path) -> Option<GameState> {
     let data = fs::read(path).ok()?;
     let gs: GameState = serde_json::from_slice(&data).ok()?;
-    if gs.schema_version != GAME_STATE_SCHEMA_VERSION {
-        return None;
-    }
     if gs.is_won { None } else { Some(gs) }
 }
 
@@ -282,7 +279,7 @@ fn cleanup_tmp_files_in(dir: &Path) {
 mod tests {
     use super::*;
     use crate::stats::{StatsExt, StatsSnapshot};
-    use solitaire_core::game_state::DrawMode;
+    use solitaire_core::DrawMode;
     use std::env;
 
     fn tmp_path(name: &str) -> PathBuf {
@@ -380,7 +377,7 @@ mod tests {
 
     #[test]
     fn game_state_round_trip() {
-        use solitaire_core::game_state::{DrawMode, GameState};
+        use solitaire_core::game_state::GameState;
         let path = gs_path("round_trip");
         let _ = fs::remove_file(&path);
 
@@ -409,7 +406,7 @@ mod tests {
 
     #[test]
     fn save_game_state_skips_won_games() {
-        use solitaire_core::game_state::{DrawMode, GameState};
+        use solitaire_core::game_state::GameState;
         let path = gs_path("won_skip");
         let _ = fs::remove_file(&path);
 
@@ -424,7 +421,7 @@ mod tests {
 
     #[test]
     fn delete_game_state_removes_file() {
-        use solitaire_core::game_state::{DrawMode, GameState};
+        use solitaire_core::game_state::GameState;
         let path = gs_path("delete");
         let gs = GameState::new(1, DrawMode::DrawOne);
         save_game_state_to(&path, &gs).expect("save");
@@ -442,7 +439,7 @@ mod tests {
 
     #[test]
     fn save_game_state_is_atomic() {
-        use solitaire_core::game_state::{DrawMode, GameState};
+        use solitaire_core::game_state::GameState;
         let path = gs_path("atomic");
         let gs = GameState::new(55, DrawMode::DrawThree);
         save_game_state_to(&path, &gs).expect("save");
@@ -510,7 +507,7 @@ mod tests {
     #[test]
     fn game_state_v4_mid_game_round_trip() {
         use solitaire_core::KlondikePile;
-        use solitaire_core::game_state::{DrawMode, GameState, GAME_STATE_SCHEMA_VERSION};
+        use solitaire_core::game_state::GameState;
 
         let path = gs_path("v4_mid_game");
         let _ = fs::remove_file(&path);
@@ -557,7 +554,6 @@ mod tests {
         let loaded = load_game_state_from(&path)
             .expect("a valid in-progress game must load without error");
 
-        assert_eq!(loaded.schema_version, GAME_STATE_SCHEMA_VERSION);
         assert_eq!(
             loaded, gs,
             "all pile layouts and counters must be identical after schema-v4 round-trip",
@@ -574,7 +570,7 @@ mod tests {
     /// u8-to-named conversion for `DstFoundation` / `DstTableau` indices.
     #[test]
     fn game_state_v3_migrates_to_v4() {
-        use solitaire_core::game_state::{DrawMode, GameState, GAME_STATE_SCHEMA_VERSION};
+        use solitaire_core::game_state::GameState;
 
         let path = gs_path("v3_migrate");
         let _ = fs::remove_file(&path);
@@ -599,12 +595,6 @@ mod tests {
         let loaded = load_game_state_from(&path)
             .expect("schema v3 must be accepted and migrated to v4");
 
-        // After migration, the in-memory schema version must be current.
-        assert_eq!(
-            loaded.schema_version, GAME_STATE_SCHEMA_VERSION,
-            "migrated game must report current schema version",
-        );
-
         // The loaded game should match a fresh game that had one draw applied.
         let mut expected = GameState::new(42, DrawMode::DrawOne);
         expected.draw().expect("draw must succeed on a fresh game");