feat: Introducing allocation profiler

[IlyasShabi]

What does this PR do?:
This PR adds optional allocation profiling support to the heap profiler. Allocation profiling is enabled only when passing the allocation flag to

pprof.heap.start(intervalBytes, stackDepth, true);

When enabled, the native profiler starts V8 heap sampling with allocation tracking flags so collected objects are retained in the sampling profile. The resulting pprof profile produces sample types:

• inuse_objects/count
• alloc_objects/count
• inuse_space/bytes
• alloc_space/bytes

This requires Node.js 26+, because the V8 sample API needs sample.is_live to distinguish live objects from collected ones. Older Node versions keep existing heap profiler behavior and reject allocation mode.

Motivation:
Node.js Allocation Profiler

Additional Notes:

• This feature works only with stop v1 since we will get rid of lazy load node in stopV2 soon.
• In ts/src/heap-profiler.ts I removed heapStackDepth variable because it was not used correctly.

How to test the change?:

• Add C++ unit test for BuildAllocationStatsByNodeId
• Allocation profiler unit tests in TS side were added

[github-actions]

Overall package size

Self size: 2.19 MB
Deduped: 2.55 MB
No deduping: 2.55 MB

Dependency sizes

| name | version | self size | total size | |------|---------|-----------|------------| | source-map | 0.7.6 | 185.63 kB | 185.63 kB | | pprof-format | 2.2.1 | 163.06 kB | 163.06 kB | | node-gyp-build | 4.8.4 | 13.86 kB | 13.86 kB |

_{🤖 This report was automatically generated by heaviest-objects-in-the-universe}