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

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

tests/main/migrate-v11.test.ts

@@ -0,0 +1,20 @@
+import { describe, it, expect, afterEach } from 'vitest'
+import { DatabaseSync } from 'node:sqlite'
+import { migrate } from '../../src/main/db/migrate'
+import type { SqliteDb } from '../../src/main/db/types'
+
+describe('migrate v11', () => {
+  let db: SqliteDb
+  afterEach(() => db?.close())
+
+  it('UT-MIG-11: fresh database migrates to v11 with undo_stack', () => {
+    db = new DatabaseSync(':memory:')
+    migrate(db)
+    const version = db.prepare('SELECT MAX(version) AS v FROM schema_version').get() as { v: number }
+    expect(version.v).toBe(11)
+    const table = db
+      .prepare("SELECT name FROM sqlite_master WHERE type='table' AND name='undo_stack'")
+      .get()
+    expect(table).toBeTruthy()
+  })
+})