Add Nani

[catnose99]

Types of Changes

• New addition to list
• Fixing bug in existing item in list
• Removing item from list
• Changing structure (organization) of list

Proposed Changes

This PR adds "Nani", an AI-powered translation app for macOS, to the Translation Tools section.

• Nani is an AI translator that not only translates text but also teaches you how to express ideas more naturally in context.
• Unlike traditional translators like DeepL or Google Translate, Nani explains alternative phrasing and tone differences, helping users learn as they translate.
• It’s designed for macOS and supports instant translation via shortcut keys, with an interface optimized for quick, educational translation.

Why it should be added:
Nani brings a new, educational approach to translation on macOS, focusing on improving language skills through interactive AI feedback rather than just providing static translations.

PR Checklist

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