feat(core): integrate klondike v0.3.0 / card_game v0.4.0 — solver + serde newtypes

Step 6: replace 767-line DFS seed-solver with Session<Klondike>::solve().
- try_solve_with_first_move() now delegates to card_game::Session::solve()
  with solve_moves_budget/solve_states_budget from SolverConfig
- Maps Ok(Some) → Winnable, Ok(None) → Unwinnable, Err → Inconclusive
- try_solve_from_state() retains the DFS (pile mapping pending, step 2)
- Removed dead SolverState::initial() — no longer needed for seed path
- Updated tests: session solver returns no Unwinnable in 0..500 range
  (all non-Winnable deals are Inconclusive); updated engine seed-retry test

Step 7: SavedInstruction serde newtypes in klondike_adapter.
- SavedInstruction mirrors KlondikeInstruction with Serialize+Deserialize
- Sub-types: SavedDstFoundation, SavedDstTableau, SavedKlondikePile,
  SavedKlondikePileStack, SavedTableauStack, SavedTableau, SavedFoundation,
  SavedSkipCards — all with serde derives
- From<KlondikeInstruction> for SavedInstruction (infallible)
- TryFrom<SavedInstruction> for KlondikeInstruction (InvalidSavedInstruction
  on out-of-range u8 values)
- InvalidSavedInstruction error type via thiserror

Also: chore(deps): bump klondike to v0.3.0, card_game to v0.4.0 (Cargo.toml/lock)

All 1399 tests pass; clippy clean.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Cargo.toml

@@ -37,8 +37,8 @@ solitaire_core   = { path = "solitaire_core" }
 solitaire_sync   = { path = "solitaire_sync" }
 solitaire_data   = { path = "solitaire_data" }
 solitaire_engine = { path = "solitaire_engine" }
-klondike         = { version = "0.2.0", registry = "Quaternions" }
-card_game        = { version = "0.3.0", registry = "Quaternions" }
+klondike         = { version = "0.3.0", registry = "Quaternions" }
+card_game        = { version = "0.4.0", registry = "Quaternions" }
 
 # Bevy with `default-features = false` to avoid the unused
 # `bevy_audio → rodio + symphonia + cpal 0.15 + alsa 0.9` chain.