Add Ghostty terminal reference

[DivInstance]

Summary

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

---

Changes

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

---

Rationale

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

---

Notes

• Docs-only change
• Ready for review

---

Meta

• Closes readme: add ghostty terminal ref #2569
• Hacktoberfest: This PR is a documentation contribution.

[withfig-bot]

Thank you for your submission, we really appreciate it. Like many open-source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution. You can sign the CLA by just posting a Pull Request Comment same as the below format.

---

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

---

_{You can retrigger this bot by commenting recheck in this Pull Request. Posted by the CLA Assistant Lite bot.}

[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?

Please add a 👍 as a reaction to this comment to show that you read this.

[DivInstance]

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