Add Vector - privacy-focused encrypted messenger

Vector is an open-source, NIP-17 compliant private messenger built on
Nostr with NIP-44 encryption and zero metadata leakage. Available for
Windows, macOS, Linux, and Android.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -317,6 +317,8 @@ Websites with lists of relays and their performance/health:
 - [Treasures](https://treasures.to/) - Discover HiddenTreasures. Join the decentralized geocaching adventure powered by Nostr. Hide geocaches, find them, and connect with explorers worldwide.
 - [uBlog](https://github.com/nodetec/ublog) ![stars](https://img.shields.io/github/stars/nodetec/ublog.svg?style=social) - A minimalist blog on nostr that allows anyone to easily create their own personal micro-blog.
   - [u-blog.vercel.app](https://u-blog.vercel.app)
+- [Vector](https://github.com/VectorPrivacy/Vector)![stars](https://img.shields.io/github/stars/VectorPrivacy/Vector.svg?style=social) - A privacy-focused encrypted messenger built on Nostr using NIP-17, with zero metadata leakage. Available for Windows, macOS, Linux, and Android.
+  - [vectorapp.io](https://vectorapp.io)
 - [Votestr](https://votestr.com/)![stars](https://img.shields.io/github/stars/vilm3r/votestr.svg?style=social) - Poll web app with nostr authentication and blind signature unlinkability
 - [Voyage](https://github.com/dluvian/voyage)![stars](https://img.shields.io/github/stars/dluvian/voyage.svg?style=social) - Lightweight Android client with a Reddit-like UI
 - [Wherostr](https://github.com/mapboss/wherostr_social)![stars](https://img.shields.io/github/stars/mapboss/wherostr_social.svg?style=social) - A decentralized geo-social for iOS & Android.