feat(api): listUploads 会话条目内嵌照片预览（现签 thumb/browse）

- 契约 UploadSessionPhoto 增可选 preview（PhotoPreview；旧客户端零 break）
- list() 批量查 photo_variants，uploader 视角签发：thumb+browse 齐备且
  未隐藏/删除才签（「隐藏是运营动作」口径从严；无变体→字段缺省）
- presign 本地 SigV4 无网络开销，TTL 同全局 900s
- 顺手修 batch-ops ⑦：交接后上传 bytes 撞查重改 71007（登记旧账清偿）

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

services/api/test/uploads.e2e-spec.ts

@@ -876,6 +876,72 @@ describe('uploads renew & complete & history (e2e)', () => {
     expect(bad.body.code).toBe(ErrorCodes.VALIDATION_FAILED);
   });
 
+  it('GET /uploads preview：变体齐备且未隐藏/删除 → 现签 thumb/browse；无变体或 hidden → 无 preview 字段', async () => {
+    // C-happy：补齐 thumb/browse 变体 + ready/published → 应签发。
+    await prisma.photo_variants.createMany({
+      data: (['thumb', 'browse'] as const).map((variant) => ({
+        photoId: cHappy.photoId,
+        variant,
+        objectKey: `photo-live/dev/albums/${albumId}/variants/${cHappy.photoId}/1/${variant}.jpg`,
+        bytes: 100,
+        version: 1,
+        width: 480,
+        height: 300,
+      })),
+    });
+    await prisma.photos.update({
+      where: { id: cHappy.photoId },
+      data: { processingState: 'ready', visibility: 'published' },
+    });
+    // C-bytes：变体齐备但 hidden → 不签（「隐藏是运营动作」，历史回退占位）。
+    await prisma.photo_variants.createMany({
+      data: (['thumb', 'browse'] as const).map((variant) => ({
+        photoId: cBytes.photoId,
+        variant,
+        objectKey: `photo-live/dev/albums/${albumId}/variants/${cBytes.photoId}/1/${variant}.jpg`,
+        bytes: 100,
+        version: 1,
+        width: 480,
+        height: 300,
+      })),
+    });
+    await prisma.photos.update({
+      where: { id: cBytes.photoId },
+      data: { processingState: 'ready', visibility: 'hidden' },
+    });
+
+    const res = await listUploads(memberToken, { limit: 10 });
+    expect(res.status).toBe(200);
+    type Item = {
+      clientTaskId: string;
+      photo: {
+        preview?: {
+          thumb: { url: string; expiresAt: string };
+          browse: { url: string; expiresAt: string };
+        };
+      };
+    };
+    const byTask = new Map<string, Item>(
+      (res.body.items as Item[]).map((i) => [i.clientTaskId, i]),
+    );
+
+    // 签发：URL 含变体对象键 + 签名参数；expiresAt 为 ISO 时间串。
+    const happy = byTask.get('C-happy')!;
+    expect(happy.photo.preview).toBeDefined();
+    expect(happy.photo.preview!.thumb.url).toContain(
+      `/variants/${cHappy.photoId}/1/thumb.jpg?`,
+    );
+    expect(happy.photo.preview!.browse.url).toContain(
+      `/variants/${cHappy.photoId}/1/browse.jpg?`,
+    );
+    expect(typeof happy.photo.preview!.thumb.expiresAt).toBe('string');
+
+    // 无变体（未处理）与 hidden → 无 preview 字段（App 回退占位图标）。
+    expect(byTask.get('C-type')!.photo.preview).toBeUndefined();
+    expect(byTask.get('C-bytes')!.photo.preview).toBeUndefined();
+    expect(byTask.get('R1')!.photo.preview).toBeUndefined();
+  });
+
   it('BullMQ 入队：complete 后 photo-process 队列恰有一条对应 job（重复 complete 不重复入队）', async () => {
     // C-bytes（重试成功）与 C-happy 各完成一次 → 各入队一次；jobId 以 photoId
     // 派生去重。等待短暂时间让 enqueue 落 Redis（生产者为 await，理论即时）。