Fix ghostty theme template

[XenHat]

This follows the example at https://ghostty.org/docs/features/theme

Pull Request

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Motivation

The existing template caused errors with recent versions of Ghostty. The new template no longer produces errors.

Type of Change

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• Bug fix
• New feature
• Breaking change
• Refactoring

Related Issue

• Closes #(issue number) (if any)

Testing

Describe how you tested your changes and mark the relevant items.

• Tested on niri
• Tested on Hyprland
• Tested on sway
• Tested with different bar positions and density settings
• Tested at different interface scaling values
• Tested with multiple monitors (if applicable)

Screenshots / Videos

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Checklist

• Code follows project style guidelines
• Self-reviewed my code
• No new warnings or errors
• Documentation or comments updated (if relevant)

Additional Notes

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