Integrate local database management and IPC handlers into Electron

- Add comprehensive IPC handlers for database operations like books, chapters, characters, and conversations.
- Implement local database initialization and user data encryption.
- Update preload script paths for consistent environment handling.
- Modify `page.tsx` to initialize local database within Electron environment.
- Add new dependencies including `node-sqlite3-wasm` and `electron-rebuild`.

package.json

@@ -5,7 +5,7 @@
   "type": "module",
   "main": "dist/electron/main.js",
   "scripts": {
-    "dev": "concurrently \"next dev -p 4000\" \"wait-on http://localhost:4000 && electron -r tsx/cjs electron/main.ts\"",
+    "dev": "tsc -p tsconfig.electron.json && tsc -p tsconfig.preload.json && concurrently \"tsc -p tsconfig.electron.json -w\" \"tsc -p tsconfig.preload.json -w\" \"next dev -p 4000\" \"wait-on http://localhost:4000 && wait-on dist/electron/main.js && electron dist/electron/main.js\"",
     "build:mac": "next build && tsc --project tsconfig.electron.json && tsc --project tsconfig.preload.json && electron-builder build --mac",
     "build:win": "next build && tsc --project tsconfig.electron.json && tsc --project tsconfig.preload.json && electron-builder build --win",
     "build:linux": "next build && tsc --project tsconfig.electron.json && tsc --project tsconfig.preload.json && electron-builder build --linux",
@@ -26,6 +26,8 @@
     "concurrently": "^9.2.1",
     "electron": "^39.2.1",
     "electron-builder": "^26.0.12",
+    "electron-rebuild": "^3.2.9",
+    "electronmon": "^2.0.4",
     "tsx": "^4.20.6",
     "typescript": "^5.9.3",
     "vite": "^7.2.2",
@@ -56,6 +58,7 @@
     "next": "^16.0.3",
     "next-export-i18n": "^2.4.3",
     "next-intl": "^4.5.3",
+    "node-sqlite3-wasm": "^0.8.51",
     "postcss": "^8.5.6",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",