fix(deepseek-v4): add build.sh for simple docker build

Launcher requires build.sh as the sole entrypoint for building images.
The overlay Dockerfile needs only 'docker build .' — no version.env or
locks needed since it layers on top of aidendle94's production-3.75 image.

The build.sh also prints 'Done: <tag>' which the launcher's polling loop
uses to detect a successful build.

docker-images/deepseek-v4-flash-dspark/Dockerfile

@@ -14,6 +14,3 @@ FROM aidendle94/sparkrun-vllm-ds4-gb10:production-3.75
 
 RUN pip install --no-cache-dir --no-deps --force-reinstall nvidia-nccl-cu13==2.30.4 \
  && pip install --no-cache-dir --no-deps --force-reinstall instanttensor==0.1.9
-
-ENTRYPOINT []
-CMD ["bash"]

docker-images/deepseek-v4-flash-dspark/build.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+# Simple build for deepseek-v4-flash-dspark overlay Dockerfile.
+set -euo pipefail
+cd "$(dirname "$0")"
+TAG="${TAG:-sparkrun-vllm-ds4-gb10:fixed}"
+echo "=== Building ${TAG} ==="
+docker build --progress=plain -t "${TAG}" . 2>&1
+echo "=== Done: ${TAG} ==="