fix(replay): store the deal via upstream card_game serializers (schema v4)

Replays previously persisted only seed + moves and re-dealt the board
from the seed at playback time, so any change to the seed->deal mapping
(RNG bumps, upstream upgrades) silently invalidated every existing
replay. Schema v4 instead embeds a SessionRecording - the upstream
card_game Session serde ({config, initial_state, instructions}) - so
playback rebuilds the exact recorded board; seed/draw_mode/mode remain
caption metadata only.

- core: SessionRecording newtype delegating to Session<Klondike> serde;
  GameState::recording() / from_recording(); from_instructions_unchecked
  fixture helper; serde_json added to dev-deps (tests only)
- data: Replay v4 (recording replaces moves); v1-v3 files rejected by
  the existing version gate
- engine: win-recording and sync upload freeze game.recording();
  playback rebuilds from the recording; Playing carries the extracted
  move list (+ Box<Replay> for clippy large_enum_variant)
- wasm: replay_export() builds the full v4 upload payload so JS never
  hand-assembles it (the old game.js path hardcoded schema_version: 2
  and corrupted u64 seeds via Math.round); ReplayPlayer::from_json
  enforces schema_version == 4 with a descriptive error
- web: game.js/play.html use replay_export; replay.js surfaces player
  construction errors in the caption instead of dying silently
- server: mode validation accepts data-carrying GameMode variants
  (Difficulty uploads previously 400'd against the String field)

Both replays on prod are May-era v1 rows with empty move lists - every
shared replay was already unplayable; the viewer now says why.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

solitaire_engine/src/game_plugin/mod.rs

@@ -1062,11 +1062,16 @@ pub fn record_replay_on_win(
         if recording.moves.is_empty() {
             continue;
         }
+        // The session itself is the authoritative recording: its history
+        // holds the dealt board plus the forward instruction list (undos
+        // already popped), and it serialises via the upstream card_game
+        // serializers so playback never re-deals from the seed.
+        let session_recording = game.0.recording();
         // Recording freezes on win, so the move that triggered the
         // win condition is the last one in the list. Storing the
         // index explicitly lets the playback UI read the WIN MOVE
         // position directly instead of re-deriving it on every render.
-        let win_move_index = recording.moves.len().checked_sub(1);
+        let win_move_index = session_recording.len().checked_sub(1);
         let replay = Replay::new(
             game.0.seed,
             game.0.draw_mode(),
@@ -1074,7 +1079,7 @@ pub fn record_replay_on_win(
             ev.time_seconds,
             ev.score,
             Utc::now().date_naive(),
-            recording.moves.clone(),
+            session_recording,
         )
         .with_win_move_index(win_move_index);
         let Some(p) = path.as_ref().and_then(|r| r.0.as_deref()) else {