From Multiple Atomics to Clean Progress Tracking

Concurrent one-off scripts need progress visibility, but Grafana is overkill and a pile of atomic counters with fmt.Printf is barely readable. So I built dspc, a dead simple progress counter for Go – named counters created on first use, in-place terminal output that doesn't clobber your logs, and a lock-free copy-on-write map underneath that's at least 2x faster than a mutex under contention.…