Bust Podman layer cache to ensure Claude Code upgrades on rebuild

The `npm install -g @anthropic-ai/claude-code@latest` layer was cached
by Podman, so rebuilding via `setup-yolo.sh --build=yes` silently
reused the old version instead of fetching the latest. Add a
CLAUDE_CACHEBUST build arg (set to epoch seconds) before the npm
install layer so it is always re-evaluated.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: just-meng

images/Dockerfile

@@ -220,6 +220,8 @@ RUN if [ "$EXTRA_ENTIRE" = "1" ]; then \
     fi
 
 # Install Claude
+# Cache-bust: pass --build-arg CLAUDE_CACHEBUST=$(date +%s) to force a fresh install
+ARG CLAUDE_CACHEBUST=
 RUN npm install -g @anthropic-ai/claude-code@${CLAUDE_CODE_VERSION}
 
 # Use tini as init process to properly reap zombie processes

setup-yolo.sh

@@ -155,7 +155,7 @@ elif [ "$BUILD_MODE" = "yes" ] || [ "$IMAGE_EXISTS" = false ]; then
     echo
 
     TZ=$(timedatectl show --property=Timezone --value 2>/dev/null || echo "UTC")
-    BUILD_ARGS=(--build-arg "TZ=$TZ")
+    BUILD_ARGS=(--build-arg "TZ=$TZ" --build-arg "CLAUDE_CACHEBUST=$(date +%s)")
     if [ -n "$EXTRA_PACKAGES" ]; then
         BUILD_ARGS+=(--build-arg "EXTRA_PACKAGES=$EXTRA_PACKAGES")
     fi