battery: a --no-gpu run does not wait for the GPU lock

--gpulock serialises rugnux runs on the shared card; a run given --no-gpu (in --extra) has no card to
share, but queued behind every GPU run all the same.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PXc1zD1yxHqaR1DGdCTHL4

tools/battery/battery.py

@@ -378,7 +378,7 @@ def command(binary, e, opts, model=None):
         cmd += ["--model", model]
     cmd += opts["extra_args"]
     cmd.append(e["input_path"])
-    if opts["gpulock"]:
+    if opts["gpulock"] and "--no-gpu" not in cmd:     # a CPU run has no card to share
         cmd = [opts["gpulock"]] + cmd
     return cmd