Refactor code structure for improved readability and maintainability

workers/cpu-tasks/Dockerfile

@@ -0,0 +1,26 @@
+# Combined CPU RunPod worker: background removal (rembg) + audio denoise (ffmpeg).
+# Slim base, NO CUDA. Build context = repo root.
+FROM python:3.11-slim
+
+ENV PYTHONUNBUFFERED=1 \
+    PIP_NO_CACHE_DIR=1
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+        ffmpeg libgl1 libglib2.0-0 curl && \
+    rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# RNNoise model for ffmpeg's arnndn (falls back to afftdn if the download fails).
+RUN mkdir -p /app/models && \
+    (curl -fsSL -o /app/models/rnnoise.rnnn \
+      https://raw.githubusercontent.com/GregorR/rnnoise-models/master/beguiling-drafts-2018-08-30/bd.rnnn || \
+     echo "rnnoise model download skipped; afftdn fallback will be used")
+
+RUN pip install --upgrade pip
+COPY workers/cpu-tasks/requirements.txt .
+RUN pip install -r requirements.txt
+
+COPY workers/cpu-tasks/handler.py .
+
+CMD ["python3", "-u", "handler.py"]