[JS API] Add text_generation/benchmark_genai.js sample

[almilosz]

Description

Add new sample for js api similar to python one.
Add yargs to manage the sample arguments.
Expose PerfMetrics.add() as JavaScript doesn't support operator overloading to return custom objects like Python does.
Run sample in tests/python_tests/samples/test_benchmark_genai.py

Ticket: CVS-172877

[Copilot]

Pull Request Overview

This PR adds a JavaScript benchmark sample for LLM performance testing, similar to the existing Python benchmark. It introduces the yargs package for command-line argument parsing and exposes a new add() method on the PerfMetrics class to enable metric aggregation in JavaScript.

Key changes:

• Added benchmark_genai.js sample with comprehensive CLI options for benchmarking LLMs
• Exposed PerfMetrics.add() method in JavaScript bindings to support metric aggregation
• Updated documentation to improve clarity and consistency

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
samples/js/text_generation/benchmark_genai.js	New benchmarking sample with CLI argument parsing and performance metric collection
src/js/src/perf_metrics.cpp	Added add() method binding to enable PerfMetrics aggregation
src/js/include/perf_metrics.hpp	Added method declarations for add() and get_value()
src/js/src/helper.cpp	Added template specialization to unwrap PerfMetrics objects
src/js/include/helper.hpp	Added unwrap template function declaration
src/js/lib/pipelines/llmPipeline.ts	Added TypeScript interface for the new add() method
src/js/tests/module.test.js	Added test coverage for the new add() method
samples/js/package.json	Added yargs dependency for CLI argument parsing
samples/js/text_generation/README.md	Updated documentation for the new benchmark sample
samples/python/text_generation/README.md	Minor grammar and clarity improvements

Files not reviewed (1)

• samples/js/package-lock.json: Language not supported

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[almilosz]

Log fragment from ticket.
Log from test that was failing

[Retribution98]

It looks good, only dependencies is required to be updated or discussed

[Retribution98]

These changes were made with upcoming releases of openvino-node and openvino-genai-node in mind.

[Retribution98]

LGTM

[Copilot]

Pull Request Overview

Copilot reviewed 11 out of 12 changed files in this pull request and generated 3 comments.

Files not reviewed (1)

• samples/js/package-lock.json: Language not supported

---

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