feat: Phase 0 — monorepo 骨架 + 全表迁移 + FastAPI/Next 骨架 + CI

- uv(workspace) + pnpm monorepo；docker-compose(pg+api+web)
- SQLAlchemy 16 MVP 表 + Alembic 初版迁移(无漂移，users stub)
- FastAPI 骨架：统一错误信封(带 request_id) + structlog + /jobs/:id + OpenAPI
- Next.js 骨架：纸感主题 token + OpenAPI→TS 客户端代码生成(gen:api)
- CI(ruff/mypy/pytest + pg service + alembic 漂移校验)
- 四份设计规格(PRODUCT/UX/ARCHITECTURE/DEV_PLAN) + CLAUDE.md

apps/web/vitest.config.ts

@@ -0,0 +1,14 @@
+import { resolve } from "node:path";
+
+import { defineConfig } from "vitest/config";
+
+// 单测：纯逻辑（SSE reducer / 自动保存防抖 / 向导流程），node 环境，无需 DOM。
+export default defineConfig({
+  resolve: {
+    alias: { "@": resolve(__dirname, ".") },
+  },
+  test: {
+    environment: "node",
+    include: ["lib/**/*.test.ts"],
+  },
+});