Add ContextV2 protobuf structure

[JAORMX]

Summary

This takes a project_id by default. It also provides the functionality
to prefer a ContextV2 from a request if it's present and available.

Change Type

Mark the type of change your PR introduces:

• Bug fix (resolves an issue without affecting existing features)
• Feature (adds new functionality without breaking changes)
• Breaking change (may impact existing functionalities or require documentation updates)
• Documentation (updates or additions to documentation)
• Refactoring or test improvements (no bug fixes or new functionality)

Testing

Outline how the changes were tested, including steps to reproduce and any relevant configurations.
Attach screenshots if helpful.

Review Checklist:

• Reviewed my own code for quality and clarity.
• Added comments to complex or tricky code sections.
• Updated any affected documentation.
• Included tests that validate the fix or feature.
• Checked that related changes are merged.

[coveralls]

coverage: 52.402% (-0.006%) from 52.408%
when pulling 5e2e820 on ctx-v2
into 3afa50e on main.