Command line interface for accessing the Open Web Index shards and slices.

feat: Add query stats command for dataset statistics master

- New query stats command calculates statistics via DuckDB queries - Shows record count, URL suffix/domain distribution, date range, MIME types - Visible progress bar with file count and records processed - Supports global --format flag (table, json, jsonl) - Fixed progress bar double-counting in stats command - Updated integration tests to use fixed dataset ID - Updated documentation with stats and aggregate examples - Replace deprecated lrz:latest with lexis:latest in docs


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4 changed files