把偏好库和文风库做成可提交的种子，方便数据丢了还能合并恢复。

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

tests/library-seed-backup.test.ts

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+import { mkdtempSync, readFileSync, rmSync } from "node:fs";
+import os from "node:os";
+import path from "node:path";
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import {
+  LIBRARY_SEED_DIR,
+  restoreLibrarySeedsFromRepo,
+} from "../src/libraries/seed-backup.js";
+import {
+  listActivePreferences,
+  loadPreferenceStore,
+  savePreferenceStore,
+} from "../src/preference/store.js";
+
+const originalUserData = process.env.WRITING_AGENT_DATA_DIR;
+
+describe("library seed backup", () => {
+  let tempDir = "";
+
+  beforeEach(() => {
+    tempDir = mkdtempSync(path.join(os.tmpdir(), "wa-lib-seed-"));
+    process.env.WRITING_AGENT_DATA_DIR = tempDir;
+  });
+
+  afterEach(() => {
+    if (originalUserData === undefined) {
+      delete process.env.WRITING_AGENT_DATA_DIR;
+    } else {
+      process.env.WRITING_AGENT_DATA_DIR = originalUserData;
+    }
+    rmSync(tempDir, { recursive: true, force: true });
+  });
+
+  it("restores missing preference ids from repo seeds without overwriting", () => {
+    savePreferenceStore({
+      version: 1,
+      entries: [
+        {
+          id: "starter-no-user-ntr-victim",
+          content: "用户已改过的正文",
+          status: "active",
+          createdAt: "2026-01-01T00:00:00.000Z",
+          updatedAt: "2026-01-01T00:00:00.000Z",
+        },
+      ],
+    });
+
+    const result = restoreLibrarySeedsFromRepo();
+    expect(result.preferencesAdded).toBeGreaterThanOrEqual(1);
+
+    const store = loadPreferenceStore();
+    const kept = store.entries.find((e) => e.id === "starter-no-user-ntr-victim");
+    expect(kept?.content).toBe("用户已改过的正文");
+    expect(
+      store.entries.some((e) => e.id === "starter-default-male-hetero-yuri-ok"),
+    ).toBe(true);
+    expect(listActivePreferences().length).toBeGreaterThanOrEqual(2);
+  });
+
+  it("keeps seed files in the repository libraries directory", () => {
+    const prefSeed = path.join(LIBRARY_SEED_DIR, "preferences.json");
+    const raw = JSON.parse(readFileSync(prefSeed, "utf8")) as {
+      version: number;
+      entries: Array<{ id: string }>;
+    };
+    expect(raw.version).toBe(1);
+    expect(raw.entries.some((e) => e.id === "starter-no-user-ntr-victim")).toBe(
+      true,
+    );
+  });
+});