Set go version to 1.22, tweak coverage

[dmjb]

We have decided to exclude anything under cmd for coverage since we do not want to rely on unit testing for the CLI.

Go 1.22 reimplements the coverage tool. Unfortunately, the new implementation has a bug. Disable the new coverage logic for now.

Summary

Provide a brief overview of the changes and the issue being addressed.
Explain the rationale and any background necessary for understanding the changes.
List dependencies required by this change, if any.

Fixes #(related issue)

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: 46.504% (+5.9%) from 40.582%
when pulling 81f0c81 on go-1.22
into 9f0b994 on main.