AI 小说工坊：主编 + 作家多模型协作写作应用

- Nuxt 4 + Nuxt UI 4 + AI SDK 7 + Drizzle/SQLite
- 主编规划大纲与章节简报、选派作家；作家流式写入章节文件并实时推送前端
- 逐章确认模式（默认）与自动模式；摘要与故事记忆
- 酒馆角色卡（PNG/JSON，V1-V3）与世界书导入
- 自定义最高优先级系统提示词、审稿/修改/多版本、任务日志与提示词检视
- 模拟 LLM 服务与端到端测试脚本

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/utils/storage.ts

@@ -0,0 +1,52 @@
+import { createWriteStream, existsSync, mkdirSync, readFileSync, rmSync, type WriteStream } from 'node:fs'
+import { readFile } from 'node:fs/promises'
+import { dirname, join, relative, resolve, sep } from 'node:path'
+
+export function projectDir(projectId: string) {
+  return join(dataDir(), 'projects', projectId)
+}
+
+/** 章节文件相对 data 目录的路径，例如 projects/xxx/chapters/0003-v2.md */
+export function chapterFileRel(projectId: string, index: number, version: number) {
+  return ['projects', projectId, 'chapters', `${String(index).padStart(4, '0')}-v${version}.md`].join('/')
+}
+
+export function absPath(rel: string) {
+  const root = dataDir()
+  const p = resolve(root, rel)
+  if (p !== root && !p.startsWith(root + sep)) throw new Error('非法路径')
+  return p
+}
+
+export function openChapterWriter(rel: string): WriteStream {
+  const p = absPath(rel)
+  mkdirSync(dirname(p), { recursive: true })
+  return createWriteStream(p, { encoding: 'utf8' })
+}
+
+export async function readChapterFile(rel: string) {
+  const p = absPath(rel)
+  if (!existsSync(p)) return ''
+  return readFile(p, 'utf8')
+}
+
+export function readChapterFileSync(rel: string) {
+  const p = absPath(rel)
+  return existsSync(p) ? readFileSync(p, 'utf8') : ''
+}
+
+export function removeProjectFiles(projectId: string) {
+  const dir = projectDir(projectId)
+  if (existsSync(dir)) rmSync(dir, { recursive: true, force: true })
+}
+
+export function relToData(abs: string) {
+  return relative(dataDir(), abs).split(sep).join('/')
+}
+
+/** 统计字数：中日韩字符按 1 字，英文按单词计 */
+export function countWords(text: string) {
+  const cjk = text.match(/[㐀-鿿豈-﫿぀-ヿ가-힯]/g)?.length ?? 0
+  const latin = text.replace(/[㐀-鿿豈-﫿぀-ヿ가-힯]/g, ' ').match(/[A-Za-z0-9]+(?:['’-][A-Za-z0-9]+)*/g)?.length ?? 0
+  return cjk + latin
+}