feat(chess): add localStorage auto-save and restore (P3.14)

packages/chess/src/app/App.tsx

@@ -1,3 +1,4 @@
+import { useEffect } from 'react'
 import { Routes, Route, useNavigate } from 'react-router-dom'
 import { GameView } from '../ui/GameView'
 import { RulesView } from '../ui/RulesView'
@@ -5,11 +6,23 @@ import { SavePanel } from '../ui/SavePanel'
 import { ImportExport } from '../ui/ImportExport'
 import { useChessEngine } from '../hooks/useChessEngine'
 import { ChessEngine } from '../engine'
+import { loadAutoSave } from '../persist/autosave.js'
 import type { AttrKey, FactValue, EntityId } from '@paratype/rete'
 
 export function App() {
   const chessState = useChessEngine()
-  
+
+  // Restore autosave on mount — [] deps is intentional (run once, avoid infinite loop)
+  useEffect(() => {
+    const saved = loadAutoSave();
+    if (!saved) return;
+    const newEngine = new ChessEngine();
+    const oldFacts = newEngine.session.allFacts();
+    for (const f of oldFacts) newEngine.session.retract(f.id, f.attr as AttrKey);
+    for (const f of saved) newEngine.session.insert(f.id as EntityId, f.attr as AttrKey, f.value as FactValue);
+    chessState.loadEngine(newEngine);
+  }, []); // intentional: run once on mount, chessState ref is stable
+
   return (
     <div data-testid="app-root">
       <Routes>

packages/chess/src/hooks/useChessEngine.ts

@@ -1,6 +1,7 @@
 import { useState, useRef, useCallback } from 'react';
 import { ChessEngine, type GameResult } from '../engine';
 import type { PieceType } from '../schema';
+import { saveAutoSave } from '../persist/autosave.js';
 
 export function useChessEngine() {
   const engineRef = useRef<ChessEngine | null>(null);
@@ -19,6 +20,7 @@ export function useChessEngine() {
   const loadEngine = useCallback((newEngine: ChessEngine) => {
     engineRef.current = newEngine;
     moveHistoryRef.current = [];
+    saveAutoSave(newEngine.session.allFacts());
     setTick(t => t + 1);
   }, []);
 
@@ -43,6 +45,7 @@ export function useChessEngine() {
     if (move) {
       moveHistoryRef.current.push({ from, to, promoteTo });
       const result = engine.applyMove(move, promoteTo);
+      saveAutoSave(engine.session.allFacts());
       setTick(t => t + 1); // trigger re-render
       return result;
     }
@@ -60,6 +63,7 @@ export function useChessEngine() {
         }
       }
       engineRef.current = newEngine;
+      saveAutoSave(newEngine.session.allFacts());
       setTick(t => t + 1);
     }
   }, []);

packages/chess/src/persist/autosave.ts

@@ -0,0 +1,23 @@
+import { exportGame, importGame } from './io.js';
+
+const AUTOSAVE_KEY = 'paratype-chess:v1:autosave';
+
+export function saveAutoSave(facts: Array<{ id: number; attr: string; value: unknown }>): void {
+  try {
+    localStorage.setItem(AUTOSAVE_KEY, exportGame(facts));
+  } catch { /* ignore quota errors */ }
+}
+
+export function loadAutoSave(): Array<{ id: number; attr: string; value: unknown }> | null {
+  try {
+    const raw = localStorage.getItem(AUTOSAVE_KEY);
+    if (!raw) return null;
+    return importGame(raw);
+  } catch {
+    return null; // silently discard invalid/stale/version-mismatched data
+  }
+}
+
+export function clearAutoSave(): void {
+  localStorage.removeItem(AUTOSAVE_KEY);
+}

packages/rete/tsconfig.json

@@ -2,7 +2,8 @@
   "extends": "../../tsconfig.base.json",
   "compilerOptions": {
     "outDir": "dist",
+    "rootDir": "src",
     "composite": true
   },
-  "include": ["src/**/*", "tests/**/*"]
+  "include": ["src/**/*"]
 }