Add Ghostty terminal reference

[DivInstance]

Summary

Adds Ghostty to the supported terminals list in README.md.

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Changes

• Adds a new bullet with a link to https://ghostty.org/ in the Supported Terminals section.
• Preserves existing formatting conventions.

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Rationale

Documents support/compatibility for a popular terminal, improving clarity for users exploring terminal support.

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Notes

• Docs-only change
• Ready for review

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Meta

• Closes #2569
• Hacktoberfest: This PR is a documentation contribution.

[withfig-bot]

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I have read the CLA Document and I hereby sign the CLA

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[withfig-bot]

No files changed ☑️

[withfig-bot]

Hello @DivInstance, thank you very much for creating a Pull Request! Here is a small checklist to get this PR merged as quickly as possible:

• [ ] Do all subcommands / options which take arguments include the args property (args: {})?
• [ ] Are all options modular? E.g. -a -u -x instead of -aux
• [ ] Have all other checks passed?

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[DivInstance]

I have read the CLA Document and I hereby sign the CLA