feat: 实现笔临 P0/P1 Electron 桌面应用 v0.1.0

交付写作核心（TipTap、自动保存、分卷分章）、Onboarding、7 主题与双语 i18n、快捷键设置；主进程使用 node:sqlite；补全 Vitest 与 Playwright E2E；统一 design/ 目录并移除 desigin 拼写错误路径。

Co-authored-by: Cursor <cursoragent@cursor.com>

src/main/ipc/result.ts

@@ -0,0 +1,18 @@
+import { ErrorCode, type IpcError, type IpcResult } from '../../shared/types'
+
+export function ok<T>(data: T): IpcResult<T> {
+  return { ok: true, data }
+}
+
+export function fail(code: ErrorCode, message: string, recoverable: boolean): IpcResult<never> {
+  return { ok: false, error: { code, message, recoverable } }
+}
+
+export function wrap<T>(fn: () => T, recoverable = true): IpcResult<T> {
+  try {
+    return ok(fn())
+  } catch (e) {
+    const message = e instanceof Error ? e.message : String(e)
+    return fail(ErrorCode.UNKNOWN, message, recoverable)
+  }
+}