create JSON strings larger than 512MB in javascript

• big-json
• json-stream-stringify
• json-stream-es
• har-json-stringify is a custom serializer for HAR data. surprisingly, this is slower than the general-purpose solutions

• JSONStream - throws RangeError: Invalid string length
• concatjson - throws RangeError: Invalid string length
• ndjson - only works for newline-delimited JSON
• stream-json - JSON.parse only

• JSON.stringify fails after 1.052 seconds
• big-json done after 1.52 seconds
• json-stream-stringify done after 1.917 seconds
• json-stream-es done after 2.076 seconds
• har-json-stringify done after 2.048 seconds

• also verify correct JSON output by piping to jq
• benchmark different types of data, for example deeply-nested arrays