List Hubble datasets

{  "database": "stellar_hubble",  "coverage": {    "completedRanges": [      {        "firstLedger": "2",        "lastLedger": "63489999"      },      {        "firstLedger": "63490304",        "lastLedger": "63490367"      }    ],    "contiguousFirstLedger": "2",    "contiguousLastLedger": "63489999",    "contiguousLedgerCount": "63489998",    "supplementalLedgerCount": "64",    "totalLedgerCount": "63490062",    "nextLedger": "63490000",    "minimumLedger": "2",    "maximumLedger": "63490367",    "gapCount": 1  },  "datasets": [    {      "columns": [        {          "name": "transaction_hash",          "position": 1,          "type": "String"        }      ],      "name": "history_transactions",      "rowCount": "25000000"    }  ],  "generatedAt": "2026-07-15T16:44:00.000Z",  "ingestion": {    "completedBatches": "62002",    "failedBatches": "0",    "startedBatches": "1",    "minimumLedger": "2",    "maximumLedger": "63490367",    "totalRows": "125000000"  },  "officialSchemaSource": "stellar/stellar-etl"}