初始提交：抖音视频批量采集流水线

App 端免签名接口（设备注册 + detail + CDN 直链），一体化流水线
下载→抽音→传COS→记录→删本地，AI 作品四档判定，四份文档：
README（使用指南）、PROGRESS（批次进度）、RE（逆向全过程）、AI（判定规则）。

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

douyin/__init__.py

@@ -0,0 +1,37 @@
+"""抖音单视频无水印下载。"""
+
+from .app import AppClient, Device, DeviceRegisterError, NotAVideo
+from .batch import BatchStats, run_batch
+from .client import (
+    Aweme,
+    DouyinClient,
+    DouyinError,
+    LoginRequired,
+    decode_abort,
+    play_url_from_uri,
+)
+from .cos import CosError, CosUploader, SizeMismatch
+from .download import Registry, download, safe_filename
+from .meta import RecordLog, build_record, iter_records, split_desc
+from .signer import (
+    ABogusConfig,
+    ABogusSigner,
+    NodeSigner,
+    SignError,
+    Signer,
+    SignerNotConfigured,
+)
+from .urls import ParseError, extract_aweme_id
+
+__all__ = [
+    "AppClient", "Device", "DeviceRegisterError", "NotAVideo",
+    "BatchStats", "run_batch",
+    "Aweme", "DouyinClient", "DouyinError", "LoginRequired", "decode_abort",
+    "play_url_from_uri",
+    "Registry", "download", "safe_filename",
+    "CosError", "CosUploader", "SizeMismatch",
+    "RecordLog", "build_record", "iter_records", "split_desc",
+    "ABogusConfig", "ABogusSigner", "NodeSigner", "SignError", "Signer",
+    "SignerNotConfigured",
+    "ParseError", "extract_aweme_id",
+]