util: add maxObjectProperties option to inspect - #65242

Add maxObjectProperties to util.inspect so callers can cap how many named properties are formatted per inspected value, independently from maxArrayLength.

The default is Infinity, so existing output is unchanged unless the option is set. Own string and symbol properties are shown before user-defined prototype properties. Entries governed by maxArrayLength and built-in metadata such as [byteLength], [buffer], and [BYTES_PER_ELEMENT] do not count toward the limit. Omitted properties are not evaluated, so getters and [util.inspect.custom] on truncated keys are skipped. The limit is applied before sorted. Assertion errors pass maxObjectProperties: Infinity explicitly so changes to inspect.defaultOptions do not affect assertion diffs.

Examples

Regular object

const obj = { first: 1, second: 2, third: 3 };
util.inspect(obj);
// '{ first: 1, second: 2, third: 3 }'
util.inspect(obj, { maxObjectProperties: 2 });
// '{ first: 1, second: 2, ... 1 more property }'

Array with custom properties

Array indices are governed by maxArrayLength; named properties on the array use maxObjectProperties:

const arr = [1, 2];
arr.first = 3;
arr.second = 4;
util.inspect(arr);
// '[ 1, 2, first: 3, second: 4 ]'
util.inspect(arr, { maxArrayLength: 1, maxObjectProperties: 1 });
// '[ 1, ... 1 more item, first: 3, ... 1 more property ]'

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