Tests: improve compatibility with Node.js

Tests: improve compatibility with Node.js

Accept RangeError from Buffer.concat() revalidation.
Remove oversized Buffer.from() cases that make Node.js allocate 4 GiB.
Expect empty Buffer.fill() values to fail.
Use fs.rm() for recursive removal under Node.js.
Check non-enumerable fs.Stats date properties directly.
Use distinct readlink fixtures for concurrently run test cases.

Known failures for js_test --binary=node are limited to module
resolution in import and XML module tests for v25.2.1 on linux.