feat(netflow-db): add merge-shards and a cluster launcher for day-sharded reprocessing#106

fix(netflow-db): merge compact MAAD tables and require matching q grids

fix(scripts): spread launcher shards across every slot and host

fix(netflow-db): track consumed shards and reconcile start dates during merges

feat(scripts): consume local shard copies during the launcher merge

feat(netflow-db): add a consuming merge mode that bounds peak disk

fix(scripts): run cluster shards detached and name them by day range

refactor(netflow-db): merge shards one attachment at a time and require full marker coverage

fix(scripts): deploy cluster files atomically and cap launcher slots

fix(netflow-db): keep the merge error when temporary cleanup cannot resolve paths

feat(scripts): add ssh launcher for day-sharded pipeline runs

feat(netflow-db): add merge-shards for day-sharded products