refactor: replace local DrawMode with upstream klondike::DrawStockConfig (#82)

DrawMode was a 1:1 mirror of klondike::DrawStockConfig (DrawOne/DrawThree).
Delete it and use the upstream type everywhere; re-export DrawStockConfig from
solitaire_core. config_for assigns draw_stock directly and draw_mode() returns
session.config().inner.draw_stock.

Serde is unchanged — DrawStockConfig serialises to the same "DrawOne"/"DrawThree"
named variants, so persisted game_state.json / replay JSON stay byte-compatible
(no migration). Field/method/variable names containing draw_mode are unchanged.

35 files, mechanical type swap across all crates. Implemented via a multi-agent
workflow (core → per-crate consumers → verify). cargo test --workspace and
clippy --workspace --all-targets -- -D warnings green.

Closes #82

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

solitaire_engine/src/replay_overlay/tests.rs

@@ -2,7 +2,7 @@ use super::*;
 use chrono::NaiveDate;
 use solitaire_core::{Foundation, KlondikePile, Tableau};
 use solitaire_core::card::{Rank, Suit};
-use solitaire_core::{DrawMode, game_state::GameMode};
+use solitaire_core::{DrawStockConfig, game_state::GameMode};
 use solitaire_core::klondike_adapter::{SavedKlondikePile, SavedTableau};
 use solitaire_data::{Replay, ReplayMove};
 
@@ -13,7 +13,7 @@ use solitaire_data::{Replay, ReplayMove};
 fn synthetic_replay(move_count: usize) -> Replay {
     Replay::new(
         42,
-        DrawMode::DrawOne,
+        DrawStockConfig::DrawOne,
         GameMode::Classic,
         120,
         1_000,
@@ -2314,7 +2314,7 @@ fn format_suit_glyph_all_suits() {
 fn format_foundations_row_empty_board() {
     let game = solitaire_core::game_state::GameState::new_with_mode(
         42,
-        solitaire_core::DrawMode::DrawOne,
+        solitaire_core::DrawStockConfig::DrawOne,
         solitaire_core::game_state::GameMode::Classic,
     );
     assert_eq!(format_foundations_row(&game), "F: -- -- -- --");
@@ -2326,7 +2326,7 @@ fn format_foundations_row_empty_board() {
 fn format_stock_waste_row_initial_state() {
     let game = solitaire_core::game_state::GameState::new_with_mode(
         42,
-        solitaire_core::DrawMode::DrawOne,
+        solitaire_core::DrawStockConfig::DrawOne,
         solitaire_core::game_state::GameMode::Classic,
     );
     let text = format_stock_waste_row(&game);