fix: 图生视频节点进度解析兼容百分号格式，K26/K3/Seedance统一走cf-api异步接口，K26新增seed参数

- 修复 K_video_image2video.py 进度值 "10%" 解析报错：rstrip('%') 后 float→int 安全转换
- K26 节点拆分为图生视频/首尾帧两个独立节点，删除旧的合并节点 K_video.py
- K26/K3 视频节点及 Seedance 客户端统一改用 get_async_api_base_url (cf-api.o1key.com)
- K3 节点模式选项从 标准/专家 改为 720p/1080p，与后端一致
- K_video_image2video.py 和 K_video_firstlast.py 新增 ComfyUI 原生 seed 参数

Co-Authored-By: Claude Opus 4.6 <[email protected]>

utils/r2_uploader.py

@@ -18,7 +18,8 @@ async def _presign(filename: str, content_type: str) -> tuple:
     api_key = get_api_key_or_raise()
     base_url = get_api_base_url()
 
-    async with aiohttp.ClientSession() as session:
+    connector = aiohttp.TCPConnector(ssl=False)
+    async with aiohttp.ClientSession(connector=connector) as session:
         async with session.post(
             f"{base_url}/v1/storage/presign",
             headers={"Authorization": f"Bearer {api_key}"},
@@ -35,7 +36,8 @@ async def _presign(filename: str, content_type: str) -> tuple:
 
 async def _put_upload(upload_url: str, data: bytes, content_type: str):
     """用预签名 URL 直传文件到 R2（不带 Authorization）"""
-    async with aiohttp.ClientSession() as session:
+    connector = aiohttp.TCPConnector(ssl=False)
+    async with aiohttp.ClientSession(connector=connector) as session:
         async with session.put(
             upload_url,
             data=data,