feat: ship v1.2.0 Wave 1 foundation with book settings, chapter management, and focus mode

Deliver schema v9, book/chapter IPC extensions, BookSettingsTab, chapter meta/tags,
AI session menu, focus mode and TTS, template context enrich, and Wave 1 E2E coverage.

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

e2e/book-settings.spec.ts

@@ -0,0 +1,43 @@
+import { mkdtempSync, rmSync, existsSync } from 'fs'
+import { join } from 'path'
+import { tmpdir } from 'os'
+import { test, expect } from '@playwright/test'
+import { launchApp, skipOnboarding, createBookAndOpenEditor, openBookSettings } from './helpers'
+
+test.describe('Book settings', () => {
+  let userDataDir: string
+
+  test.beforeEach(() => {
+    userDataDir = mkdtempSync(join(tmpdir(), 'bilin-e2e-book-settings-'))
+  })
+
+  test.afterEach(() => {
+    if (userDataDir && existsSync(userDataDir)) {
+      try {
+        rmSync(userDataDir, { recursive: true, force: true, maxRetries: 3, retryDelay: 200 })
+      } catch {
+        /* ignore */
+      }
+    }
+  })
+
+  test('E2E-BOOK-01: rename book, always cockpit, delete book', async () => {
+    const app = await launchApp(userDataDir)
+    const page = await app.firstWindow()
+    await skipOnboarding(page)
+    await createBookAndOpenEditor(page, '原始书名')
+
+    await openBookSettings(page)
+    await page.getByTestId('book-settings-name').fill('改后书名')
+    await page.getByTestId('book-settings-always-cockpit').check()
+    await page.getByTestId('book-settings-save').click()
+    await expect(page.locator('.sidebar-header')).toContainText('改后书名', { timeout: 10_000 })
+
+    page.once('dialog', (dialog) => dialog.accept())
+    await page.getByTestId('book-settings-delete').click()
+    await expect(page.locator('#home-page')).toBeVisible({ timeout: 15_000 })
+    await expect(page.getByText('改后书名')).toHaveCount(0)
+
+    await app.close()
+  })
+})