This PR implements the following new nodetool commands: * netstats * tablehistograms/cfhistograms * proxyhistograms All commands come with tests and all tests pass with both the new and the current nodetool implementations. Refs: https://github.com/scylladb/scylladb/issues/15588 Closes scylladb/scylladb#17651 * github.com:scylladb/scylladb: tools/scylla-nodetool: implement the proxyhistograms command tools/scylla-nodetool: implement the tableshistograms command tools/scylla-nodetool: introduce buffer_samples utils/estimated_histogram: estimated_histogram: add constructor taking buckets tools/scylla-nodetool: implement the netstats command tools/scylla-nodetool: add correct units to file_size_printer