chore(instrumentation): add helpers for Git instrumentation

[jamietanna]

Changes

As part of being able to fully instrument our Git operations - using
SimpleGit - we can introduce some Git-specific instrumentation helpers.

These helpers will be used as part of a future change, where we will
instrument methods of SimpleGit that we're using.

This provides a set of types which will be used as OpenTelemetry
Attributes to categorise command types.

A number of subcommands that aren't currently deemed to be too important
are bucketed into an other category.

---

Note that it's worth reviewing this with the integration (#39591) in mind)

Context

Please select one of the below:

• This closes an existing Issue: #
• This doesn't close an Issue, but I accept the risk that this PR may be closed if maintainers disagree with its opening or implementation

AI assistance disclosure

Did you use AI tools to create any part of this pull request?

Please select one option and, if yes, briefly describe how AI was used (e.g., code, tests, docs) and which tool(s) you used.

• No — I did not use AI for this contribution.
• Yes — minimal assistance (e.g., IDE autocomplete, small code completions, grammar fixes).
• Yes — substantive assistance (AI generated non‑trivial portions of code, tests, or documentation).
• Yes — other (please describe):

Documentation (please check one with an [x])

• I have updated the documentation, or
• No documentation update is required

How I've tested my work (please select one)

I have verified these changes via:

• Code inspection only, or
• Newly added/modified unit tests, or
• No unit tests but ran on a real repository, or
• Both unit tests + ran on a real repository

The public repository:

[github-actions]

🎉 This PR is included in version 42.27.5 🎉

The release is available on:

• GitHub release
• 42.27.5

Your semantic-release bot 📦🚀