GenAI spec updates for langchain

[nagkumar91]

Description

This PR renames the package to opentelemetry-instrumentation-langchain-v2 and updates the collector to the latest spec.
This allows us to release the package as the official opentelemetry package.

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Test A

Does This PR Require a Core Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[zhirafovod]

@wrisa, can you review it and propose the plan to implement in the opentelemetry-util-genai instead?

[wrisa]

@wrisa, can you review it and propose the plan to implement in the opentelemetry-util-genai instead?

@nagkumar91 we have latest WIP genai utils where all the semantic convention aligned telemetry can be moved.
Please see the proposal here: https://docs.google.com/document/d/1w9TbtKjuRX_wymS8DRSwPA03_VhrGlyx65hHAdNik1E/edit?tab=t.qneb4vabc1wc#heading=h.kh4j6stirken
Here is an example: https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3768/files#diff-ceaf683887146bf95f37a7ebb888621d695e881d6e69059e4c7b3a9bc0120f9bR50

[rads-1996]

defined twice

[xrmx]

one has - and the other _

[nagkumar91]

@wrisa, can you review it and propose the plan to implement in the opentelemetry-util-genai instead?

@nagkumar91 we have latest WIP genai utils where all the semantic convention aligned telemetry can be moved. Please see the proposal here: https://docs.google.com/document/d/1w9TbtKjuRX_wymS8DRSwPA03_VhrGlyx65hHAdNik1E/edit?tab=t.qneb4vabc1wc#heading=h.kh4j6stirken Here is an example: https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3768/files#diff-ceaf683887146bf95f37a7ebb888621d695e881d6e69059e4c7b3a9bc0120f9bR50
@zhirafovod @wrisa
Is there some sample code I can run to see if the spans/traces I care about are captured?
If its still in design/ideation, can we get this change merged? I can help out with implementing changes once the proposal gets merged.