Stop corrupted machine_metrics.jsonl from breaking build uploads

Fixed an intermittent failure (TUIST-10W) where uploading a build could crash the server’s build processor with a bad-CRC error on machine_metrics.jsonl, causing runs to be retried and never complete. The CLI now snapshots the live metrics file under the metrics sampler’s shared lock before bundling it into the build archive, so the copy no longer races the always-on sampler daemon. The tuist bundle/build-upload flow is now consistent with respect to the daemon’s writes.