support node --enable-source-maps usage with our custom Error.prepareStackTrace usage

[trentm]

As of Node.js v21.6.0, node's internal prepareStackTrace function that handles source-map conversion for stack traces -- for the --enable-source-maps CLI option -- is exposed (as Error.prepareStackTrace).

That means that it should be possible chain our prepareStackTrace handling (which we use for parsing details from an exception for error reporting), with the core Node.js one when the user has used this CLI option.

[trentm]

See the long notes and discussion at #2833

[trentm]

Actually I was looking at details here for a customer support issue, and I believe we do work with node --enable-source-maps ... in versions of node that include nodejs/node#50827

This is because it was exposed as Error.prepareStackTrace and our prepareStackTrace code (in error-callsites) will use that: https://github.com/watson/error-callsites/blob/917208c601c88fcec2abb4dc3bdc17655f75e45b/index.js#L7

So Node.js versions v20.12.0, v21.6.0, and later should just work.
In versions before that a started elastic-apm-node agent will break node --enable-source-maps ....