feat: inpaint MASK input + MaskScaleBy node + i2i mask plumbing

QuantFunc Image List 节点新增:
- main_image_mask (MASK):触发 inpaint。白=重绘,黑=保留(对齐 ComfyUI
  SetLatentNoiseMask)
- mask_strength / mask_grow / mask_blur / mask_no_snap:辅助调节
  (对齐 MaskBlur / GrowMask / VAEEncodeForInpaint.grow_mask_by 默认 6)
- 自动把 mask 缩放到主图尺寸,免去外部 mask resize 节点
- 输入命名整理:image1 → main_image,image2..10 → ref_image_2..10,
  ref_img_resize → main_image_resize,ref_img_resize_others → ref_image_resize_others
  英文命名+中文 tooltip,内部 dict key 保留旧名兼容 Generate 节点

QuantFunc Mask Scale By 节点(新):
- 对称 ComfyUI 自带 ImageScaleBy(自带的不接 MASK 类型),scale_by 同步
  用法:LoadImageMask → MaskScaleBy → main_image_mask
- 三种插值:bilinear / nearest / bicubic

worker.py:
- I2IParams ctypes struct 加 5 个 mask 字段(对齐 include/quantfunc.h)
- handle_image_to_image 从 msg 读 mask_path/strength/grow/blur/no_snap,
  传给 C API。无 mask 时所有字段保持 NULL/默认 = 不触发 inpaint

WorkerManager.image_to_image: 接受 mask kwargs,通过 JSON cmd 传给 worker

(本提交也包含此前未推的 unload_modes 策略整理)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>