feat(w5): ship v2.0.0 platform sync, undo persistence, and updates

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

tests/main/update.service.test.ts

@@ -0,0 +1,25 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest'
+import { UpdateService } from '../../src/main/services/update.service'
+
+describe('UpdateService', () => {
+  const prevMock = process.env.BILIN_MOCK_UPDATE
+  const prevVersion = process.env.BILIN_MOCK_UPDATE_VERSION
+
+  beforeEach(() => {
+    process.env.BILIN_MOCK_UPDATE = '1'
+    process.env.BILIN_MOCK_UPDATE_VERSION = '9.9.9'
+  })
+
+  afterEach(() => {
+    if (prevMock === undefined) delete process.env.BILIN_MOCK_UPDATE
+    else process.env.BILIN_MOCK_UPDATE = prevMock
+    if (prevVersion === undefined) delete process.env.BILIN_MOCK_UPDATE_VERSION
+    else process.env.BILIN_MOCK_UPDATE_VERSION = prevVersion
+  })
+
+  it('IT-UPDATE-01: mock check returns available version', async () => {
+    const svc = new UpdateService()
+    const info = await svc.check()
+    expect(info?.version).toBe('9.9.9')
+  })
+})