[corbob]

NOTE: This PR is draft as I need it to run in GitHub Actions to see if it's fixed the build.

Description Of Changes

• Change the macos-build job in .github/workflows/build.yml and .github/workflows/test.yml from runs-on: macos-14 to runs-on: macos-latest.
• Add an Install Mono step to both macOS jobs that runs brew install mono and then mono --version. It runs before the dotnet setup, the same way the Ubuntu jobs install Mono before building.

Motivation and Context

The macOS jobs were pinned to macos-14 in 17682ea as a temporary workaround. Newer macOS runner images don't include Mono, so the build couldn't run on them.

That workaround no longer works: GitHub retired the macos-14 images on November 2, 2026, so the pinned jobs can no longer run. macos-latest now points to the macOS 26 Arm64 image. That image still doesn't include Mono, but it does include Homebrew, and the Homebrew mono formula (6.14.1) has a ready-built package for macOS 26 on Arm64. Installing Mono at the start of the job lets the builds run on macos-latest, so they will keep up with future runner image updates instead of being pinned to a version that will be retired.

Testing

1. TODO(author): Record the result of the macos-build job in the Chocolatey Builds workflow on this PR. That run on macos-latest is the test for this change.
2. TODO(author): Optionally, run the Chocolatey Integration Tests workflow (test.yml) by hand and record the macos-build result. It only runs on a schedule or by manual dispatch, so the PR won't run it automatically.

Operating Systems Testing

• macOS 26 (Arm64), GitHub Actions macos-latest runner, through this PR's CI. TODO(author): confirm once the run completes.

Change Types Made

• Bug fix (non-breaking change).
• Feature / Enhancement (non-breaking change).
• Breaking change (fix or feature that could cause existing functionality to change).
• Documentation changes.
• PowerShell code changes.

Change Checklist

• Requires a change to the documentation.
• Documentation has been updated.
• Tests to cover my changes, have been added.
• All new and existing tests passed?
• PowerShell code changes: PowerShell v3 compatibility checked?
• Significant design decisions: ADR has been created by a Chocolatey team member?
• All items are complete on the Definition of Done.

Related Issue

Fixes #3785