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>

src/main/ipc/handlers/ai.handler.ts

@@ -1,5 +1,6 @@
 import { randomUUID } from 'crypto'
-import { BrowserWindow, ipcMain } from 'electron'
+import { writeFileSync } from 'fs'
+import { BrowserWindow, dialog, ipcMain } from 'electron'
 import { IPC } from '../../../shared/ipc-channels'
 import type { AiConfig, AiContextBinding, NamingConflict } from '../../../shared/types'
 import { BookRegistryService } from '../../services/book-registry'
@@ -19,6 +20,15 @@ import { wrap } from '../result'
 
 const activeChats = new Map<string, AbortController>()
 
+function formatSessionMarkdown(title: string, messages: { role: string; content: string; createdAt: string }[]): string {
+  const lines = [`# ${title || 'AI 会话'}`, '']
+  for (const msg of messages) {
+    const label = msg.role === 'user' ? '用户' : msg.role === 'assistant' ? '助手' : msg.role
+    lines.push(`## ${label}`, '', msg.content, '', `_${msg.createdAt}_`, '')
+  }
+  return lines.join('\n')
+}
+
 export function registerAiHandlers(
   registry: BookRegistryService,
   settings: GlobalSettingsService,
@@ -67,6 +77,39 @@ export function registerAiHandlers(
       wrap(() => registry.getAiSessionRepo(bookId).listMessages(sessionId))
   )
 
+  ipcMain.handle(
+    IPC.AI_SESSION_EXPORT,
+    async (
+      _e,
+      {
+        bookId,
+        sessionId,
+        format = 'markdown'
+      }: { bookId: string; sessionId: string; format?: 'markdown' | 'txt' }
+    ) =>
+      wrap(async () => {
+        const repo = registry.getAiSessionRepo(bookId)
+        const session = repo.get(sessionId)
+        if (!session) throw new Error('AI session not found')
+        const messages = repo.listMessages(sessionId)
+        const text =
+          format === 'markdown'
+            ? formatSessionMarkdown(session.title, messages)
+            : messages
+                .map((m) => `[${m.role}] ${m.createdAt}\n${m.content}`)
+                .join('\n\n---\n\n')
+
+        const ext = format === 'markdown' ? 'md' : 'txt'
+        const { canceled, filePath } = await dialog.showSaveDialog({
+          defaultPath: `${session.title || 'ai-session'}.${ext}`,
+          filters: [{ name: format === 'markdown' ? 'Markdown' : 'Text', extensions: [ext] }]
+        })
+        if (canceled || !filePath) return null
+        writeFileSync(filePath, text, 'utf8')
+        return filePath
+      })
+  )
+
   ipcMain.handle(
     IPC.AI_BUILD_CONTEXT,
     (_e, { bookId, binding }: { bookId: string; binding: AiContextBinding }) =>