Refactor code structure for improved readability and maintainability

workers/upscale/Dockerfile

@@ -0,0 +1,34 @@
+FROM nvidia/cuda:12.1.1-cudnn8-runtime-ubuntu22.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+ENV PIP_NO_CACHE_DIR=1
+ENV PYTHONUNBUFFERED=1
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+        python3 python3-pip python3-dev \
+        libgl1 libglib2.0-0 wget ca-certificates \
+    && rm -rf /var/lib/apt/lists/* \
+    && ln -sf /usr/bin/python3 /usr/bin/python
+
+WORKDIR /app
+
+# Newer CUDA-12.1 torch so the compiled kernels cover current GPUs (fixes
+# "no kernel image is available for execution on the device"). The basicsr
+# functional_tensor import (removed in torchvision>=0.16) is handled by the
+# sed-patch below instead of pinning an old torchvision.
+RUN pip install --upgrade pip && \
+    pip install torch==2.1.2 torchvision==0.16.2 \
+        --index-url https://download.pytorch.org/whl/cu121
+
+COPY workers/upscale/requirements.txt .
+RUN pip install -r requirements.txt
+
+# Robustly fix basicsr's removed torchvision import (the #1 Real-ESRGAN crash).
+# Works whether or not the torch/torchvision pin held — rewrites the bad import.
+RUN F=$(python3 -c 'import basicsr,os;print(os.path.join(os.path.dirname(basicsr.__file__),"data","degradations.py"))') && \
+    sed -i 's/from torchvision.transforms.functional_tensor import rgb_to_grayscale/from torchvision.transforms.functional import rgb_to_grayscale/' "$F" && \
+    echo "patched basicsr degradations.py"
+
+COPY workers/upscale/handler.py .
+
+CMD ["python3","-u","handler.py"]