Report heap snapshots as unsupported under record/replay

[Andarist]

Heap contents differ between recording and replaying, so the snapshot serializer already emits "{}" under record/replay, but the snapshot was still generated first. On a big heap that is one native call long enough for a replaying process to be considered hung. getHeapSnapshot()'s stream also never ended, and worker.getHeapSnapshot() crashed on exit.

Fail every entry point before generating anything:

• v8.writeHeapSnapshot() and v8.getHeapSnapshot() throw ERR_RECORD_REPLAY_UNSUPPORTED, and worker.getHeapSnapshot() rejects with it.
• The --heapsnapshot-signal listener emits a warning instead, since throwing from it would crash the process.
• --heapsnapshot-near-heap-limit doesn't install its callback and prints a notice to stderr. It isn't a process warning because console messages logged while bootstrapping crash replaying processes that collect console messages.
• The inspector's HeapProfiler.takeHeapSnapshot and stopTrackingHeapObjects return an error.