fix(client/v2): fix comment parsing (backport #19377)

[mergify]

Description

ref: #19376

Follow-up of #18324

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Author Checklist

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please add links to any relevant follow up issues.

I have...

• included the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• reviewed "Files changed" and left comments if necessary
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• updated the relevant documentation or specification, including comments for documenting Go code
• confirmed all CI checks have passed

Reviewers Checklist

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your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix in the PR title
• confirmed all author checklist items have been addressed
• reviewed state machine logic, API design and naming, documentation is accurate, tests and test coverage

Summary by CodeRabbit

• New Features

  • Introduced new message structures for signing arbitrary data, enhancing the protocol's flexibility.
  • Added sample request message functionality and related definitions to improve testing and development workflows.
  • Implemented version information and method name constants for improved code clarity and maintenance.

• Documentation

  • Added descriptive comments to sample request messages for better understanding and usage.

• Refactor

  • Updated logic in utility functions to handle edge cases more effectively, ensuring robust support determination.
  • Refactored test cases for increased readability and efficiency.

• Tests

  • Expanded testing suite with new tests and test cases for utility functions, bolstering code reliability.

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This is an automatic backport of pull request #19377 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of ed6b3ab has failed:

On branch mergify/bp/release/v0.50.x/pr-19377
Your branch is up to date with 'origin/release/v0.50.x'.

You are currently cherry-picking commit ed6b3ab7b.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   client/v2/CHANGELOG.md
	modified:   client/v2/internal/testpb/msg.proto
	modified:   client/v2/internal/testpb/msg.pulsar.go
	modified:   client/v2/internal/testpb/msg_grpc.pb.go
	modified:   client/v2/internal/testpb/query.pulsar.go
	modified:   client/v2/internal/testpb/query_grpc.pb.go
	modified:   client/v2/internal/util/util.go
	modified:   client/v2/internal/util/util_test.go

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   client/v2/internal/offchain/msgSignArbitraryData.pulsar.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally