chore(ci): Harmonize macOS runner platform for Nix workflow

[jerome-benoit]

No description provided.

[github-actions]

Hey! Your PR title ci: Harmonize macOS runner platform for Nix workflow doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

See CONTRIBUTING.md for details.

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

No duplicate PRs found

[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
2. Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

[Copilot]

Pull request overview

This PR updates the macOS runner specification in the Nix desktop workflow to explicitly use the Intel variant, harmonizing it with the naming convention used in other workflows.

Changes:

• Changed macos-15 to macos-15-intel to explicitly specify the Intel architecture runner

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[jerome-benoit]

unneeded