fix: chunk size limit + keep MP3s + Respond Accepted fix; add rocinante stack

- Chunk Text: word-level fallback for sentences > 600 chars
- watch.py: keep MP3 after transcription
- Respond Accepted: remove cross-node reference
- rocinante/: Whisper CUDA + watcher stack for RTX 4090 transcription

rocinante/watcher/Dockerfile

@@ -0,0 +1,12 @@
+FROM python:3.12-slim
+
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends ffmpeg && \
+    rm -rf /var/lib/apt/lists/*
+
+RUN pip install --no-cache-dir watchdog requests
+
+COPY watch.py /app/watch.py
+WORKDIR /app
+
+CMD ["python", "-u", "watch.py"]