Add envx (#168)

<!-- Thanks for making Ratatui awesome! 🐭 -->

* Link to your project (GitHub/crates.io): <!-- paste here -->
https://github.com/mikeleppane/envx


* Description (optional):  <!-- short summary -->
A powerful and secure environment variable manager for developers,
featuring an intuitive Terminal User Interface (TUI) and comprehensive
command-line interface.

* Screenshot or gif (strongly recommended): <!-- drag & drop or link -->

<img width="800" height="600" alt="main"
src="https://github.com/user-attachments/assets/4261e557-ba63-4cb6-8f4b-4aa6ac7d1628"
/>

<img width="800" height="600" alt="query"
src="https://github.com/user-attachments/assets/c2ab48e4-9418-4047-869b-180c8ce0689d"
/>



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Author: mikeleppane

README.md

@@ -205,6 +205,7 @@ Aside from those listed here, many other apps and libraries can be easily be fou
 - [csvlens](https://github.com/YS-L/csvlens) - Command line csv viewer.
 - [dead-ringer](https://github.com/ztroop/dead-ringer) - Binary diff tool for Hex/ASCII analysis.
 - [diskonaut](https://github.com/imsnif/diskonaut) - Terminal-based disk space navigator.
+- [envx](https://github.com/mikeleppane/envx) - Environment variable manager for developers, featuring an intuitive TUI.
 - [exabind](https://github.com/junkdog/exabind) - An animated TUI for viewing KDE shortcuts.
 - [exhaust](https://github.com/heyrict/exhaust) - Exhaust all your possibilities for the next coming exam.
 - [flawz](https://github.com/orhun/flawz) - A TUI for browsing security vulnerabilities (CVEs).