feat(instrumentation-nats): add instrumentation nats package

[giacomoquinalia]

Which problem is this PR solving?

Initial instrumentation for NATS.

Short description of the changes

This is a continuation of the initiative started in this PR: #667. The implementation follows the architectural considerations and feedback discussed in that PR, especially the insights shared by NATS maintainers (referencing this maintainer comment).

This implementation follows the patterns and structures used in existing messaging instrumentations like kafkajs and amqplib.

Testing

The implementation has been tested locally and is functioning as expected.

• Created unit tests
• Verified the implementation by running a local script using the instrumentation-nats package and visualizing the traces in Grafana

Feedback

While the implementation is stable in my test environment, I would appreciate validation from the maintainers and the community:

1. Are there specific NATS methods or edge cases currently missing that should be prioritized for this initial release?
2. Are the concerns raised in feat: Add opentelemetry-instrumentation-nats package #667 sufficiently addressed here?

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: giacomoquinalia / name: Giácomo Quinalia (4965c82, f69d05e)

[giacomoquinalia]

A better approach for the instrumentation was suggested by a NATS maintainer in this issue and I'll update the implementation of this PR once the native support is available in the core library.

[raphael-theriault-swi]

Would you mind converting this to a draft in the meantime or closing and reopening ? This would help in making it easier to sort through GH notifications for approvers :)